GB2100256A - Xylite derivatives having a plant growth-regulating action - Google Patents

Abstract

Novel xylite derivatives of the general formula I <IMAGE> (in which R1, R2, R3 and R4 each represents H, C1-C10-alkyl optionally substituted by one or more substituents selected from Hal, C1- C6-alkoxy, phenoxy and halogenophenoxy, aryl-C1-C3-alkyl optionally substituted by one or more substituents selected from Hal, C1- C6-alkyl, C1-C6-alkoxy, -NO2 and -CF3, C3-C8-cycloaliphatic hydrocarbon, aromatic hydrocarbon optionally substituted by one or more substituents selected from Hal, C1- C6-alkyl, C1-C6-alkoxy, -NO2 and -CF3, and R1 and R2 together with adjacent C and/or R3 and R4 together with adjacent C may also represent C3-C8-cycloaliphatic hydrocarbon, R5 represents H or C1-C4-alkyl, and R6 represents aromatic hydrocarbon optionally substituted by one or more substituents selected from Hal, C1- C6-alkyl, C1-C6-alkoxy, -O-CH2- O-, phenoxy, phenyl, -NO2, -CN and -CF3) have a plant growth- regulating action, being particularly suitable for influencing the regulative and generative growth of leguminous plants e.g. soya beans.

Description

SPECIFICATION Xylite derivatives having a plant growth-regulating action and their manufacture and use The present invention is concerned with new xylite derivatives, with processes for the manufacture of these compounds and with their use as agents having a growth-regulating effect on plants.

Compounds having a growth-regulating action are already known and some have already been introduced into practical use.

One of these products which are known in practice, based on triidobenzoic acid, does indeed influence the growth of plants, but does not always have a satisfactory effect.

Another product, based on 2,3:4,6-di-O-isopropylidene-2-ketogulonic action and its sodium salt, does on the other hand lead to morphological changes in some ornamental and cultivated plants, but is limited in its application to certain plants.

The problem upon which the present invention is based has been to make available an agent which has a plant growth-regulating effect with a wide spectrum of action and at the same time causes no damage to the plants.

This problem is solved according to the present invention by the novel xylite derivatives, as defined below.

The present invention accordingly provides compounds of the general formula I

in which Rr, R2, R3 and R4 each represents a hydrogen atom, an unsubstituted C1-C10-alkyl group, a C1-C10-alkyl group substituted by one or more substituents selected from halogen atoms and C1-C8- alkoxy, phenoxy and halogenophenoxy groups, an unsubstituted aryl-C1-C3-alkyl group, an aryl-C1 C3-alkyl group substituted by one or more substituents selected from halogen atoms and C1-C6-alkyl, C1-C6-alkoxy, nitro and trifluoromethyl groups, a C3-C8-cycloaliphatic hydrocarbon group, an unsubstituted aromatic hydrocarbon group or an aromatic hydrocarbon group substituted by one or more substituents selected from halogen atoms and C1-C8-alkyl, C1-C6-alkoxy, nitro and trifluoromethyl groups, and R, and R2 together with the adjacent carbon atom may also represent a C3-C8-cycloaliphatic hydrocarbon group and/or R3 and R4 together with the adjacent carbon atom may also represent a C3C8-cycloaliphatic hydrocarbon group, R5 represents a hydrogen atom or a C1-C4-alkyl group, and R6 represents an unsubstituted aromatic hydrocarbon group or an aromatic hydrocarbon group substituted by one or more substituents selected from halogen atoms and C1-C6- alkyl, C1-C6-a Ikoxy, dioxymethylene, phenoxy, phenyl, nitro, cyano and trifluoromethyl groups.

The meanings of the symbols R,, R2, R3 and R4 may be the same or different.

The compounds of the present invention occur as optical isomers, and, if desired, also as geometrical isomers. Thus it is to be understood in the description and claims herein that when reference is made to any compound falling within the scope of the general formula I, such a compound may be in the form of such an individual isomer or of a mixture of more than one such isomers.

The compounds of the present invention are outstandingly suitable for regulating plant growth in various cultivated plants, and surprisingly surpass in their spectrum of action and also in their compatibility the products mentioned above which are known in practice and are intended to have the same effect.

Since the compounds of the present invention bring about both qualititative and quantitative changes in plants as well as changes in the metabolism of the plants, they are to be included in the class of plant growth regulators which are distinguished by the following possible applications.

Restricting vegetative growth in woody and herbaceous plants, for example on roadsides and rail tracks, in order to suppress too abundant growth. Restricting growth in cereals in order to prevent fall inc over or snapping off, and in cotton to increase yield.

Influencing the branching out of vegetative and generative organs in ornamental or cultivated plants in order to increase blossoming, or in tobacco and tomato plants to restrict the production of side-shoots.

Improving the quality of the fruit, for example increasing the sugar content of sugar cane, sugarbeet or fruit, and producing a more uniform ripening of the crop, which leads to higher yields.

Increasing the resistance to climatic influences, for example cold and dryness.

Influencing the flow of latex in rubber plants.

Formation of parthenocarpic fruits, pollen sterility and influencing of gender are also possible applications.

Controlling the germination of seeds or budding.

Defoliation or influencing fruit drop to facilitate harvesting.

The compounds of the present invention are particularly suitable for influencing the vegetative and generative growth of some leguminous plants, for example soya bean plants.

Depending on the purpose of the application, the amounts applied are generally within the range of from 0.005 to 5 kg of active substance per hectare, but larger amounts may also be used if desired.

When two or more compounds of the present invention are used, the range of 0.005 to 5 kg per hectare refers of course to the total application quantities.

The time of application depends on the purpose of application and the climatic conditions.

Of the compounds of the present invention, those which are particularly distinguished by the effects described are those compounds of the general formula I in which R1, R2, R3 and R4 have the same or different meanings and in each case represents a hydrogen atom or a methyl, ethyl, propyl, isopropyl, n-butyl, sec.-butyl, tert.-butyl, 2,2-dimethyl-1 -propyl, n-pentyl, n-heptyl, n-octyl, n-decyl, chloromethyl, bromomethyl, fluoromethyl, dichloromethyl, trifluoromethyl, trichloromethyl, methoxymethyl, ethoxymethyl, phenoxymethyl, 4-chlorophenoxymethyl, chloroethyl, bromoethyl, 2ethoxyethyl, 2-phenoxyethyl, cyclopropyl, cyclopentyl, cyclohexyl, benzyl, 2-phenylethyl, phenyl, 2chlorophenyl, 3-chlorophenyl, 4-chlorophenyl, 3,4-dichlorophenyl, 4-methoxyphenyl, 4-nitrophenyl or 2,4-dichlorophenyl group, R5 represents a hydrogen atom or a methyl group, and R6 represents a phenyl, 2-chlorophenyl, 3-chlorophenyl, 4-chlorophenyl, 2,6-dichlorophenyl, 4-dichlorophenyl, 3,4dichlorophenyl, 2,4,6-trichlorophenyl, 4-bromophenyl, 2,4-dibromophenyl, 2,6-dibromophenyl, 2,4,6tribromophenyl, 2-fluorophenyl, 3-fluorophenyl, 4-fluorophenyl, 2,4-difluorophenyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 3,4-dimethylphenyl, 2-methoxyphenyl, 3-methoxyphenyl, 4methoxyphenyl, 3,4-dioxymethylene-phenyl, 2-phenoxyphenyl, 3-phenoxyphenyl, 2-nitrophenyl, 3nitrophenyl or 4-nitrophenyl group.

The following compounds should be mentioned as having an outstanding action: 5-O-(2,6-dichlorobenzyl)- 1,2 :3,4-bis-0-isopropylidenexylite, 5-0-(2,6-dich lorobenzyl)- 1,2 :3,4-bis-O-(ethyl-methyl-methylene)-xylite and 5-0-(2,6-dichlorobenzyl)- 1,2 :3,4-bis-0-(methyl-propyl-methylene)-xylite.

The present invention accordingly also provides a preparation for regulating the growth of plants, which comprises at least one compound of the general formula I in admixture or conjunction with a suitable carrier.

The present invention further provides a method of regulating the growth of a living plant, wherein the living plant and/or the area in the vicinity of the living plant is/are treated with a compound of the general formula I.

The present invention further provides a method of regulating the growth of plants in an area of land, for example a crop area, wherein the area is treated with a compound of the general formula I.

The present invention further provides a method of dressing seeds, wherein the seeds are treated with a compound of the general formula I.

The present invention further provides a pack which comprises a compound of the general formula I, together with instructions for its use in regulating the growth of living plants.

The compounds of the present invention may be applied singly, or in the form of mixtures with each other or with other active substances. If desired, other defoliants, plant-protecting agents and/or pesticides may be added, depending on the desired purpose of application.

If the intention is to widen the range of action, other biocides may also be added. For example, there are suitable as such active substances herbicidally active co-components from the groups of triazines, aminotriazoles, anilides, diazines, uracils, aliphatic carboxylic acids and halo-carboxylic acids, substituted benzoic acids and arylcarboxylic acids, hydrazides, amides, nitriles and esters of such carboxylic acids, carbamic acid esters and thiocarbamic acid esters, ureas, 2,3,6-trichlorobenzyloxypropanil, thiocyanate-containing agents and other additives.

Among other additives there are to be understood, for example, also non-phytotoxic additives that are capable of producing, with herbicides, a synergistic increase in action, for example wetting agents, emulsifiers, solvents and oily additives.

The active compounds of the present invention or mixtures thereof are advantageously used in the form of preparations, for example powders, strewable preparations, granules, solutions, emulsions or suspensions, with the addition of liquid and/or solid vehicles or diiuents and, if desired, of surfaceactive agents, for example wetting, adhesion-promoting, emulsifying and/or dispersing agents.

Suitable liquid carriers are, for example, water, aliphatic hydrocarbons, aromatic hydrocarbons, for example benzene, toluene and xylene, cyclohexanone, isophorone, dimethyl sulphoxide and dimethylformamide, and also mineral oil fractions.

Suitable solid carriers are, for example, mineral earths, for example tonsil, silica gel, talc, kaolin, attaclay, limestone and silicic acid, and vegetable products, for example meals.

As surface-active agents there may be mentioned, for example, calcium lignin-sulphonate, polyoxyethylene-alkylphenol ethers, naphthalene-sulphonic acids and salts thereof, phenol-sulphonic acids and salts thereof, formaldehyde condensates, fatty alcohol sulphates and also substituted benzene-sulphonic acids and salts thereof.

The total amount of the active substance or substances in the various preparations may vary within wide limits. For example, the preparations may contain from approximately 10 to 80% by weight of active substance(s), from approximately 90 to 20% by weight of liquid or solid carrier and also, if desired, up to 20% by weight of surface-active agent(s).

The active substances may be applied in the usual manner, for example with water as carrier in spray liquor amounts ranging from approximately 100 to 1000 litres per hectare. It is also possible to apply the active substances by the so-called low-volume method and ultra-low-volume method and it is equally possible to apply them in the form of so-called micro-granules.

The following components, for example, are used to produce the preparations: Table I A. Spray powder a) 40% by weight of active substance 25% by weight of clay minerals 20% by weight of highly dispersed silicic acid 10% by weight of cellulose pitch 5% by weight of surface-active agents based on a mixture of the calcium salt of lignin-sulphonic acid and alkylphenol-polyglycol ethers.

b) 25% by weight of active substance 60% by weight of kaolin 10% by weight of highly dispersed silicic acid 5% by weight of surface-active agents based on the sodium salt of N-methyl-N-oleyl-taurine and the calcium salt of lignin-sulphonic acid.

c) 10% by weight of active substance 60% by weight of clay minerals 15% by weight of highly dispersed silicic acid 10% by weight of cellulose pitch 5% by weight of surface-active agents based on the sodium salt of N-methyl-N-oleyl-taurine and the calcium salt of lignin-sulphonic acid.

B. Paste 45% by weight of active substance 5% by weight of sodium aluminium silicate 1 5% by weight of cetylpolyglycol ether with 8 moles of ethylene oxide 2% by weight of spindel oil 10% by weight of polyethylene glycol 23 parts of water.

C. Emulsion concentrate 25% by weight of active substance 15% by weight of cyclohexanone 55% by weight of xylene 5% by weight of a mixture of nonylphenyl-polyoxyethylene and calcium dodecyl-benzene sulphonate.

The new compounds of the present invention may be manufactured, for example, by the processes of the present invention, as defined below.

The present invention accordingly further provides a process for the manufacture of the compounds of the general formula 1, wherein A) a compound of the general formula Il

is reacted with a compound of the general formula Ill

in the presence of an acid-binding agent, R1, R2, R3, R4, R5 and Re having the meanings given above and one of the symbols X and Y representing a halogen atom, preferably a chlorine or bromine atom, and the other symbol representing an -OH group, or B) a compound of the general formula II is reacted with a compound of the general formula lil, R1, R2, R3, R4, R5 and R6 having the meanings given above and one of the symbols X and Y representing a halogen atom, preferably a chlorine or bromine atom, and the other symbol representing an -OZ group, in which Z represents an alkali metal atom, preferably a sodium, potassium or lithium atom, or a monovalent alkaline earth metal equivalent, or C) a compound of the general formula IV

in which R5 and R6 have the meanings given above, is reacted a) with compounds of the general formulae V and VI

in which R1, R2, R3 and R4 have the meanings given above, in the presence of an acid catalyst and/or a dehydrating agent, or b) with compounds of the general formulae VII and VIII

in which R1, R2, R3 and R4 have the meanings given above and R7, R8, R9 and R10 each represents a C1- C4-alkyl group, in the presence of an acid catalyst.

The meanings of the symbols R7, R8, R9 and R10 may be the same or different.

When one of the symbols X and Y represents a hydroxyl group, the reaction according to process A is carried out in the presence of a base, advantageously an alkali metal hydroxide, alkali metal alcoholate, alkali metal hydride or alkali metal carbonate, preferably a sodium compound.

A preferred embodiment of process A is the reaction of a compound of the general formula II, in which Y represents a hydroxyl group, with a compound of the general formula III, in which X represents a halogen atom, preferably a chlorine or bromine atom, in the presence of a base, for example sodium hydride or sodium hydroxide.

The reaction between the reactants takes place between 0 and 1 500C, but generally at a temperature between room temperature and the reflux temperature of the particular reaction mixture.

The compounds of the general formulae II and Ill may be manufactured by means of known methods.

For the synthesis of the compounds of the present invention the reactants are used in approximately equivalent amounts. Solvents which are inert with respect to the reactants are suitable reaction media. The choice of the solvent or suspension medium depends on the particular benzyl halides used, the acid acceptors used and any metal compounds used.

As solvents or suspension media there may be mentioned, for example, ethers, for example diethyl ether, diisopropyl ether, tetrahydrofuran and dioxan, aliphatic and aromatic hydrocarbons, for example petroleum ether, cylcohexane, hexane, heptane, benzene, toluene and xylene, carboxylic acid nitriles, for example acetonitrile, and carboxylic acid amides, for example dimethylformamide.

The reactants, may, however, themselves serve the function of a solvent.

For binding the particular hydrohalic acids there are used tertiary amines, for example triethylamine or N,N-dimethylaniline, and pyridine bases, or, preferably suitable for the purpose, inorganic bases, for example oxides, hydroxides, hydrides, carbonates and alcoholates of the alkali metals and alkaline earth metals.

The etherification of the xylite compounds of the general formula II with benzyl halides of the general formula Ill, in which again Y represents a hydroxyl group and X represents a halogen atom, may also be carried out in a manner known per se by phase transfer catalysis. This procedure makes it possible to manufacture the compounds of the present invention in a simpler manner and in a higher yield with the use of inexpensive materials.

For this purpose, according to the present invention a benzyl halide of the general formula

is reacted in a two-phase system, consisting of a xylite compound of the general formula Ill, diluted if desired with an inert solvent, and of an alkali hydroxide, either solid or in the form of an aqueous solution, in the presence of a catalyst. Of the hydroxides, sodium hydroxide is preferred, preferably in the form of a 50% aqueous solution.

Suitable catalysts are onium compounds, for example quaternary ammonium, phosphonium and arsonium compounds, and also sulphonium compounds.

Also suitable are polyglycol ethers, especially cyclic ethers, for example 1 8-crown-6, and tertiary amines, for example tributylamine. Preferred compounds are quaternary ammonium compounds, for example benzyl-triethyl-ammonium chloride and tetrabutylammonium bromide.

The proportions of the reactants may vary within wide limits. The reactions are preferably carried out with a 1-10 times excess of the benzyl halide and a 1-10 times excess of the hydroxide. 0.02 equivalent of the catalyst is sufficient.

The reaction takes place at a temperature between 20 and 1 000C, but generally between 20 and 600 C. The duration of the reaction is from 1 to 72 hours. During the entire reaction time thorough mixing is necessary.

The process variants described above also apply when compounds of the general formula ll, in which Y represents a halogen atom, are reacted with compounds of the general formula III, in which X represents a hydroxyl group.

For the synthesis of the compounds of the present invention according to process C, the reactants are used in approximately equimolar amounts; the carbonyl compounds V and VI or the acetal or ketal compounds VII and VIII may of course also be used in excess, as quasisolvents, without any disadvantage. The reaction takes place in the presence of dehydrating agents as well as in the presence of acid catalysts, for example copper sulphate, zinc chloride, ammonium chloride, sulphuric acid, ptoluene-sulphonic acid, boron trifluoride-diethyl ether complex, hydrogen chloride and phosphorus pentoxide. Suitable reaction media are solvents which are inert with respect to the reactants.As examples of these there may be mentioned halogenated hydrocarbons, for example methylene chloride, chloroform and carbon tetrachloride, aliphatic and aromatic hydrocarbons, for example pentane, hexane, heptane, cyclohexane, benzene, toluene and xylene, and the reacting ketones and aldehydes as well as the ketals and acetals themselves.

The reaction takes place at a temperature between 0 and 1000C, but generally between room temperature and the reflux temperature of the particular reaction mixture. The duration of the reaction is from 1 to 72 hours.

The compounds of the present invention manufactured according to the processes described above may be isolated from the reaction mixture by the usual procedures, for example by distilling off the solvent used under normal or reduced pressure, by precipitation with water, or by extraction. A greater degree of purity may generally be obtained by purification by means of column chromatography, and also by fractional distillation under reduced pressure.

In general, the compounds of the present invention are almost colourless and odourless liquids which are soluble with difficulty in water, soluble to a certain extent in aliphatic hydrocarbons, for example petroleum ether, hexane, pentane and cyclohexane, and readily soluble in halogenated hydrocarbons, for example chloroform, methylene chloride and carbon tetrachloride, aromatic hydrocarbons, for example benzene, toluene and xylene, ethers, for example diethyl ether, tetrahydrofuran and dioxan, carboxylic acid nitriles, for example acetonitrile, ketones, for example acetone, alcohols, for example methanol and ethanol, carboxylic acid amides, for example dimethylformamide, and sulphoxides, for example dimethyl sulphoxide.

As already mentioned, the compounds of the present invention occur as optical isomers, and, if desired, also as geometrical isomers. the individual isomers and mixtures thereof are also included within the scope of the present invention.

The following Examples illustrate the invention. These Examples illustrate the manufacture of the compounds of the present invention.

Example 1 5-0-(2,4-Dichlorobenzyl )-1 ,2 :3,4-b is-O-isopropylidene-xyl ite 116.13 g (0.5 mole of 1 ,2:3,4-bis-O-isopropylidene-xylite were placed together with 97.74 g (0.5 mole) of 2,4-dichlorobenzyl chloride and 4.5 g (0.019 mole) of benzyl-triethylammonium chloride. A solution of 100 g of sodium hydroxide (2.5 moles) in 125 ml of water was added dropwise thereto at room temperature while stirring extremely thoroughly, in the course of which the temperature rose slowly to approximately 500C and then fell again to room temperature in the course of approximately one hour.

Stirring was then continued for another hour at room temperature in order to complete the reaction, after which the whole was diluted with 500 ml of ice-water and extracted three times using 1 50 ml of ethyl acetate for each extraction. The organic phase was washed twice using 300 ml of water for each wash, dried over magnesium sulphate, filtered and concentrated by evaporation in vacuo at 400 C. The oil which remained behind was subjected to fractional distillation.

Yield: 168.2 g=86.1% of the theoretical yield B.P.005 torr:159-16l0C;no20: 1.5078 TLC: Eluting agent=toluene/ethyl acetate 4:1 Rf-value: 0.52 Analysis: Calculated: C 55.25n e H 6.18% Cl 18.12% Found: C 55.62% H 6.42% CII 17.88% The abbreviation TLC is used herein to mean thinlayer chromatography.

Example 2 5-0-(2,6-Dichlorobenzyl)-1,2 :3,4-bis-0-isopropylidene-xylite A solution of 23.2 g (0.1 mole) of 1 ,2:3,4-bis-0-isop ropyliden e-xylite in 100 ml of toluene was slowly added dropwise, while stirring, to a suspension of 2.88 g (0.12 mole) of sodium hydride in 50 ml of toluene. After the addition was completed, the mixture was heated under reflux for two hours. A solution of 1 9.54 g (0.1 mole) of 2,6-dichlorobenzyl chloride in 50 ml of toluene was then added dropwise thereto and the mixture was heated under reflux for a further five hours. After cooling down, the mixture was washed three times using 1 50 ml of water for each wash; the organic phase was then dried over magnesium sulphate, filtered and evaporated in vacuo at 400C. The oil which remained behind was distilled in vacuo.

Yield: 35.8 9=91.5% of the theoretical yield B.P.1 torr 190--1980C; n20: 1.5080 TLC: Eluting agent=toluene/ethyl acetate 4:1 Rf-value: 0.50 Analysis: Calculated: C 55.25% H 6.18% Cl 18.12% Found: C 55.66% H 6.46% Cl 18.03% Example 3 5-0-(2-Chlo rb enzyl-l .2 :3,4-bis-O-isopropylidene-xylite 1.44 g (0.06 mole) of sodium hydride were carefully added to a solution of 11.64 g (0.05 mole) of 1 ,2:3,4-bis-O-isopropylidene-xylite in 30 ml of dry dimethylformamide. Stirring was then carried out for one hour at 40 , and then 8.1 g (0.05 mole) of 2-chlorobenzyl chloride were added dropwise thereto, in the course of which the temperature rose to 55 C.Stirring was continued for a further 2- hours at 50 C to complete the reaction; the whole was then carefully diluted with 150 ml of ice-water and extracted three times using 200 ml of ethyl acetate for each extraction. The ethyl acetate phase, after being dried over magnesium sulphate and filtered, was concentrated by evaporation in vacuo at 4000. The oily residue was distilled in a bulb tube (oven temperature: 160 C ; 0.1-0.05 torr).

Yield: 1 5.4 g=86.3% of the theoretical yield n20D : 1 4978 TLC: Eluting agent=toluene/ethyl acetate 4:1 R1-value : 0.50 Analysis: Calculated: C 60.57% H 7.06% Cl 9.94% Found: C 60.50% H 6.98% Cl 9.70% Example 4 5-C-(2,4-Dichlorobenzyl)-1,2,3,4-bis-O-(methyl-methylene)-xylite 9.32 g (0.03 mole) of 5-0-(2,4-dichlorobenzyl)-xylite were suspended in a solution of 9.44 g (0.08 mole) of acetaldehyde-diethyl-acetal and 30 ml of toluene, and then 1 ml of boron trifluoridediethyl ether complex was added thereto. The whole was then heated at 80 C for 30 minutes and the resulting alcohol was distilled off.After cooling, the reaction solution was washed with a saturated potassium bicarbonate solution, dried over magnesium sulphate, filtered and concentrated by evaporation in vacuo at 4000. The oil which remained behind was distilled in a bulb tube (oven temperature ; 190 C ; 0.01 torr).

Yield: 8.90 g=81.5% of the theoretical yield n20D : 1.5283 TLC: Eluting agent=chloroform/methanol 4:1 Revalue: 0.71 Analysis: Calculated: C 52.90% H 5.55% Cl 19.52% Found: C 52.97% H 5.75% Cl 19.54% The following compounds of the present invention may be manufactured in a manner analogous to that described in any one of Examples 1 to 4.

Name Physical constant 5-0-(4-Bromobenzyl)- 1,2 :3,4-bis-0-isopropylidene-xylite n20D : 1.5074 5-O-(3,4-Dichlorobenzyl)-1,2,3,4-bis-O-isopropylidene-xylite n20D : 1.5078 5-0-(4-Chlorobenzyl)- 1,2 :3,4-bis-0-isopropyiidene-xylite n,20: 1.4975 5-O-(2-Chlorobenzyl)-1,2,3,4-bls-O-lsopropylidene-xyilte n20D : 1.4978 5-O-(3-Chlorobenzyl)- 1,2 :3,4-bis-0-isopropylidene-xylite n20D : 1.5050 5-0-(2-Methylbenzyl- 1,2 :3,4-bis-0-isopropylidene-xylite n20D : 1.4904 5-O-(3-Methylbenzyl)-1,2:3,4-bis-O-isopropylidene-xylite n20D : 1.4878 5-(4-Methylbenzyl)-1,2:3 ,4-bis-0-isopropyl iden e-xylite n 20: 1 .4875 5-O-(3,4-Dimethylbenzyl)-1,2,3,4-bis-O-isopropylidene-xylite n20D : 1.4920 5-O-(2-Fluorobenzyl)- 1,2 :3,4-bis-0-isopropylidene-xylite n20D : 1.4805 5-O-(3-Fluorobenzyl)- 1,2 :3,4-bis-0-isopropylidene-xv)ite n 20: 1.4798 5-O-(4-Fluorobenzyl)-1,2,3:4-bls-O-isopropylidene-xylite n20D : 1.4789 5-O-(3-Trifluoromethylbenzyl)- 1,2 :3,4-bis-0-isopropylidene-xylite n: 1.4610 5-O-Benzyl-1,2:3.4-bis-O-Isopropylidene-xylite n20D : 1.4890 5-0-(2,4-Dichlorobenzyl)- 1,2 :3,4-bis-0-(diethyl-methylene)-xylite n20D : 1.5070 5-0-(2,6-Dichlorobenzyl)- 1,2 :3,4-bis-O-(ethyl-methyl-methylene)-xylite n Do 1.5078 5-O-(2,4-Dichlorobenzyl)-1,2:3,4-bis-O-(ethyl-methyl-methylene)-xylite n20D : 1.5060 5-O-(2-Chlorobenzyl)- 1,2 :3,4-bis-O-(ethyl-methyl-methylenen)-xyllte n 20: 1.4960 5-O-(2-Methylbenzyl)- 1 ,2 :3,4-bis-0-(ethyl-methyl-methylene)-xylite n @@@ 1 1.4847 5-O-(2,6-Dichlorobenzyl)-1,2:3,4-bis-O-(methyl-propyl-methylene)-xylite n20D : 1.5036 5-0-(2,4-Dichlorobenzyl)- 1,2 :3,4-bis-0-(methyl-propyl-m ethylene)-xylite n20D : 1.5032 5-0-(2-Methylbenzyl)- 1,2 :3,4-bis-O-(methyl-propyl-methylene)-xylite nO: 1.4884 5-O-(2-Chlorobenzyl)-1,2,3,4-bis-O-(methyl-propyl-methylene)-xylite n20D : 1.4911 5-O-(2,6-Dichlorobenzyl)-1,2:3,4-bls-O-(dlethyl-methylene)-xylite n20D : 1.5070 5-O-(2-Methylbenzyl)-1 ,2 :3,4-bis-0-(diethyl-methylene)-xylite nO: 1.4902 5-O-(2-Chlorobenzyl)- 1,2:3,4-bis-O-(diethyl-methylene)-xyllte n,20: 1.4980 5-0-(2-Methylbenzyl)-1 .2 :3,4-bis-O-(benzyl-methyl-methylene)-xylite n 20: 1 .5496 5-O-(2-Chlorobenzyl)-1,2:3,4-bis-O-(benzyl-methyl-methylene)-xylite n20D : 1.5542 5-O-(2,4-Dichlorobenzyl)-1,2:3,4-bls-O-(benzyl-methyl-methylene)-xylite n20D : 1.5568 5-O-(2,6-Dichlorobenzyl)-1,2:3,4-bis-O-(benzyl-methyl-methylene)-xylite n20D : 1.5568 5-O-(2-Methylbenzyl)-1,2:3,4-bis-O-(butyl-methyl-methylene)-xylite n20D : 1.4844 5-O-(2-Chlorobenzyl)- 1,2 :3,4-bis-0-(1,1 -tetramethylene-methylene) xylite n20D : 1.5220 Name Physical constant 5-0-(2,4-Dichlorobenzyl)- 1,2 :3,4-bis-O-(1,1 -tetramethylene methylene)xylite nD20: 1.5282 5-O-(2-Chlorobenzyl)-1,2;3,4-bis-O-(butyl-methyl-methylene)-xylite n20D : 1.4898 5-O-(2,4-Dichlorobenzyl)-1,2,:3,4-bis-O-(butyl-methyl-methylene)-xylite n20D : 1.4950 5-O-(2-Methylbenzyl)-1,2:3,4-bis-O-(1,1-tetramethylene-methylene)- xylite n20D : 1.5148 5-O-(2,6-Dichlorobenzyl)-1,2:3,4-bis-O-(butyl-methyl-methylene]-xylite n20D : 1,4946 5-O-(2,6-Dichlorobenzyl)-1,2:3,4-bis-O-(1,1-tetramethylene-methylene) xylite 5-O-(2-Chlorobenzyl)-1 ,2 :3,4-bis-0-[(2-phenylethyl)-methyl-methylene]- n20D : 1.5303 xylite n20D : 15326 5-O-(2,4-Dichlorobenzyl)-1,2,:3,4-bis-O-[(2-phenylethyl)methyl methylene]-xylite n20D : 1.5433 5-O-(2,4-Dichlorobenzyl)-1,2:3,4-bis-O-(methyl-methylene)-xylite n20D : 1.5283 5-O-(4-Phenylbenzyl)- 1,2 :3,4-bis-0-isopropylidene-xylite m.p.: 600 C 5-O-(4-Cyanobenzyl)- 1,2 :3,4-bis-0-isopropylidene-xylite m.p.: 670C 5-O-(2,6-Dichlorobenzyl)-1,2:3,4-bis-O-[(2-phenylethyl)methyl- n20D : 1.5528 methylene]-xylite 5-O-(2-Methylbenzyl)- 1,2 :3,4-bis-0-[(2-phenylethyl)-methyl-methylene]- xylite n20D : 15427 5-0-(2,6-Dichlorobenzyl)- 1,2 :3,4-bis-o-(4-chlorophenyl-methyene)-xylite m.p.: 201 OC 5-O-(2-Chlorobenzyl)-1,2:3,4-bis-O-(phenyl-methylene)-xylite m.p. : 155 C 5-O-(2,4-Dichlorobenzyl)-1,2;3,4-bis-O-(4-chlorophenyl-methylene)-xylite m.p. : 174 175 C 5-O-(2-Methylbenzyl)-1,2:3,4-bis-O-(4-chlorphenyl-methylene)-xylite m.p. : 174 C 5-0-(2,6-Dichlorobenzyl)- 1,2 :3,4-bis-0-(phenyl-methylene)-xylite m.p.: 205 C 5-O-(2,6-Dichlorobenzyl)-1,2 :3,4-bis-0-(methyl-methylene)-xylite m.p. 1120C 5-O-(2-Methylbenzyl)-1,2:3,4-bis-O-(methyl-methylene)-xylite n20D : 1.5174 5-O-(2-Chlorobenzyl)- 1,2 :3,4-bis-O-(methyl-methylene)-xylite n20D : 1.5281 5-O-(2,6-Dichlorobenzyl)-1,2:3,4-bls-O-(chloromethyl-methylene)-xyllte N20D : 1.5391 5-0-(2,4-Dichlorobenzyl)- 1,2 :3,4-bis-O-9chloromethyl-methylene)-xylite n Do 1.5358 5-O-(2-Methylbenzyl)-1,2:3,4-bls-O-(chloromethyl-methylene)-xyllte n20D : 1.5263 5-O-(2-Chlorobenzyl)-1,2:3,4-bis-O-(chloromethyl-methylene)-xylite n20D : 1.5250 5-O-(2,6-dichlorobenzyl)-1,2:3,4-bis-O-methylene-xylite m.p. : 102 C 5-0-(2,4-Dichlorobenzyl)- 1,2 :3,4-bis-0-methylene-xylite m.p.: 65-66 C 5-O-(2-Methylbenzyl)- 1,2 :3,4-bis-O-methylene-xylite n20D : 1.5267 5-0-(2,4-Dichlorobenzy)- 1,2 :3,4-bis-O-(methyl-octyl-methylene)-xylite n20D : 1.4900 5-O-(2,6-Dichlorobenzyl)-1,2,:3,4-bis-O-(methyl-octyl-methylene)-xylite n20D : 1.4921 5-O-(2-Methylbenzyl)-1,2:3,4-bis-O-(methyl-octyl-methylene)-xylite n20D : 1.4784 5-O-(2-Chlorobenzyl)- 1,2 :3,4-bis-O-(methyl-octyl-methylene)-xylite n20D 1.4852 5-O-(2,4-Dlchlorobenzyl)-1,2:3,4-bis-O-(phenyl-methylene)-xylite m.p. : 178 C 5-O-(2-Methylbenzyl-1,2:3,4-bis-O-(phenyl-methylene)-xylite m.p. : 156 15700 5-O-(2,4-Dichlorobenzyl)-1,2;3,4-bis-O-[(2,6-dichlorophenyl)-methylene] xylite m.p. : 156 C 5-O-(2-methylbenzyl)-1,2P:3,4-bis-O-[(2,6-dichlorophenyl)-methylene] xylite m.p. : 191 19200 5-O-(2-Chlorobenzyl)-1,2:3,4-bis-O-[(2,6-dichlorophenyl)-methylene] xylite m.p. : 207 208 C 5-O-(2,6-Dichlorobenzyl)-1,2:3,4-bis-O-[(2,6-dichlorophenyl)methylens] xylite m.p. : 183 184 C 5-O-(2,4,6-Tribromobenzyl)-1,2:3,4-bis-O-isopropyulidene-xylite n20D : 1.5516 5-O-(1-Phenylethyl)-1,2:3,4-bis-O-isopropylldene-xylite n20D : 1.4860 5-O-(1-(2,4-Dichlorophenyl)-ethyl]-1,2:3,4-bis-O-isopropylidene-xylite n20D : 1.5168 5-0-[1 -(2,6-Dichlorophenyl)-ethyl]- 1,2 :3,4-bis-O-isopropylidene-xylite n20D: 1.5158 5-0-(2,6-Dichlorobenzyl)- 1,2 :3,4-bis-0-(methyl-phenoxymethyl- methylene)-xylite n20D : 1.5598 5-O-(2,4-Dichlorobenzyl)-1,2,3,4-bis-O-(methyl-phenoxymethyl methylenc) xylitc n20D : 1.5579 The starting compounds used for the manufacture of the compounds of the present invention by the processes of the present invention are known per se or may be prepared according to process known per se as described in J. Chem. Soc. (London) 1965, 3382.

The following procedures illustrate the manufacture of the starting compounds.

A. Compounds of the general formula II a) 1,2 :3,4-Bis-O-(ethyl-methyl-methylene)-xylite 50 g (0.328 mole) of xylite were suspended at room temperature in 1 litre of dry ethyl methyl ketone. While stirring thoroughly, 10 ml of concentrated sulphuric acid were added thereto all at once.

Stirring was continued for 48 hours at room temperature; after approximately 5 hours all the xylite had dissolved and the reaction solution was reddish-brown in colour. When the reaction was completed, the solution was adjusted to pH 8 with approximately 50 ml of a 32% sodium hydroxide solution while stirring, in the course of which the solution lost its colour again. The aqueous phase was separated off, and the organic phase was dried over magnesium sulphate and concentrated by evaporation in a water-jet vacuum at 400 C. The residue was subjected to fractional distillation.

Yield: 63.5 g=74.4% of the theoretical yield B.P. o.s tour - 118 C ; n20D-1.457 TLC: Eluting agent=toluene/ethyl acetate 4:1 Rfvalue=0.22 Analysis: Calculated: C 59.97% H 9.29% 0 30.73% Found: C 59.50% H 9.41% 0 31.12% b) 1,2 :3,4-Bis-O-(phenyl-methylene)-xylite 30 g (0.197 mole) of xylite were suspended in 150 ml of toluene, and 71.04 g (0.393 mole) of benzaldehyde-diethyl-acetal were added thereto. Then 150 mg of p-toluene-sulphonic acid hydrate were added thereto and the reaction mixture was heated to 800C, in the course of which the xylite slowly dissolved and the reaction product crystallized out.The whole was allowed to cool, and then the crystals were filtered off with suction, then washed with 100 ml of ether, and dried to a constant weight in vacuo at 400.

Yield: 61.2 g-94.6% of the theoretical yield m.p.: 1 390C (colourless crystals) TLC: Eluting agent=chloroform/methanol 4:1 Rfvalue=0.59 Analysis: Calculated: C 69.49% H 6.14% Found: C 69.07% H 6.43% The following starting materials may be prepared in an analogous manner.

Name Physical constant 1,2 :3,4-Bis-O-isopropylidene-xylite nD : 1.4530 B.P.o mm :103-1050C m.p.: 330C 1,2 :3,4-Bis-O-(diethyl-methylene)-xylite n 20: 1.466 B.P. oA ton : 120 C 1,2:3,4-Bis-O-(benzyl-methyl-methylene)-xylite n20D : 1.542 B.P.001 torr:215-2200C 1,2:3,4-Bis-O-(methyl-propyl-methylene)-xyllte n20D : 1.547 B.P.0.3 tour : 136 C 1,2:3,4-Bis-O-[methyl-(2-phenyl-ethyl) methylene]-xylite n20D : 1.535 1,2:3,4-Bis-O-(butyl-methyl-methylene)-xylite n20D : 1.459 1 ,2 :3,4-Bis-O-( 1,1 -tetramethylene-methylene)-xylite n20D : 1.494 1.2:3,4:Bis-O-(phenyl-methylene)-xylité B.P. o.1 ton : 160 C 1,2:3,4-Bis-O-methylene-xylite m.p. : 139 C 1,2:3,4-Bis-O-(chloromethyl-methylene)-xylite n20D : 1.4816 1,2:3,4-Bis-O-(methyl-methylene)-xylite n20D : 1.4968 1,2:3,4-Bis-O-(4-chlorophenyl-methylene)-xylite m.p. : 134 -135 C 1,2:3,4-Bis-O-(methyl-octyl-methylene)-xylite m.p. : 212 - 213 C n20D : 1.4613 B. Compounds of the general formula IV 5-0-(2,4-Dichlorobenzyl)-xylite 10.2 g (0.026 mole) of 5-0-(2,4-dichlorobenzyl)-l ,2 :3,4-bis-0-isopropylidene-xylite were added to 27.7 ml of 1.5N sulphuric acid at room temperature. The whole was then heated at 700C for 2 1/2 hours while stirring thoroughly, after which the reaction solution was cooled and adjusted to pH 8 with a approximately 4 ml of a 32% sodium hydroxide solution. It was then extracted twice using 100 ml of ethyl acetate for each extraction. The organic phase was dried over magnesium sulphate, filtered and evaporated in vacuo.Colourless crystals were obtained, which were digested with 50 ml of cold diisopropyl ether. Recrystallization from toluene was carried out.

Yield: 6.4 g=79.09/o of the theoretical yield m.p.: 96-980C TLC: Eluting agent=chloroform/methanol 4:1 Rf-value=0.330 Analysis: Calculated: C 46.32% H 5.18% Cl 22.79% Found: C 46.32% H 5.27% Cl 22.45% The following starting materials may be prepared in an analogous manner: Name Physical constant 5-0-(2,5-Dichlorobenzyl)-xylite m.p.: 82-830C 5-O-(2-Chlorobenzyl)-xylite m.p.: 52-540C 5-O-(2-Methylbenzyl)-xylite m.p.:59-610C The following Examples also illustrate the invention.These Examples illustrate the possible applications for the compounds of the present invention Example 5 Growth modification in cress In a series of tests carried out in a laboratory, cress seeds were treated with the compounds of the present invention listed in the Table below, in each case in the form of an aqueous emulsion.

The concentration of the active substance in each emulsion was 100 ppm.

For this purpose, in each test a slide was placed in a 200 ml glass vessel with 10 ml of active substance emulsion. Filter paper was drawn on to the slide. When the filter paper was soaked with the emulsion, 10 cress seeds were evenly distributed over it. The lid of a petri dish was then placed on the vessel. Two glass vessels were used for each active substance.

For evaluation, the length of the shoots and roots on the germinated seeds was measured after 7 days.

The average values in cm. which were obtained in this manner can be seen from the Table. In the Table the values are given in relation to the control and expressed as percentages.

It is shown that the compounds of the present invention exert a strong influence on the growth of roots and shoots in cress. This is clearly shown by the promotion ( > 100%) or retardation ( < 100%) of the individual parts.

Growth as a Compound of the invention Shoot Root 5-O-(4-Bromobenzyl)-1 ,2 :3,4-bis-O-isopropylidene-xylite 75 138 5-0-(2,6-Dichlorobenzyl)- 1,2 :3,4-bis-0-isopropylidene-xylite 75 125 5-O-(3,4-Dichlorobenzyl)-1 2 :3,4-bis-O-isoprnpylidene-xylite 88 100 5-0-(2,4-Dichlorobenzyl)-1,2:3,4-bis-0-isopropylidene-xylite 75 88 5-O-(4-Chlorbenzyl)-1 .2 :3,4-bis-0-isopropylidene-xylite 75 275 5-0-(2-Chlorobenzyl)-1,2:3,4-bis-0-isopropylidene-xylite 88 88 113 5-O-(3-Chlorobenzyl)-1 ,2:3,4-bis-0-isopropylidene-xylite 88 200 5-O-(2-Methylbenzyl)-1 ,2:3,4-bis-0-isopropylidene-xylite 100 225 5-O-(3-Methylbenzyl)-1,2::3,4-bis-O-isospropylidene-xylite 88 138 5-0-(4-M ethylbenzyl)-l ,2:3 ,4-bis-0-isopropyl idene-xylite 88 125 5-0-(3,4-Dimethylbenzyl)-l ,2:3,4-bis-O-isopropylidene-xylite 88 200 5-O-(2-Fluorobenzyl)-1 ,2:3,4-bis-0-isopropylidene-xylite 88 250 5-O-(3-Fluorobenzyl)-1,2:3,4-bis-O-isopropylidene-xylite 88 150 5-O-(4-Fluorobenzyl)-1,2:3,4-bis-O-isopropylidene-xylite 100 113 5-O-(3-Trifluoromethylbenzyl)-1,2:3,4-bis-O-isopropylidene-xylite 71 114 5-0-Benzyl-1,2 :3,4-bis-0-isopropylidene-xylite 83 156 5-0-(2,4-Dichlorobenzyl) 1,2 :3,4-bis-(diethyl-methylene)-xylite 83 122 5-O-(2-Methylbenzyl- 1,2 :3,4-bis-0-(ethyl-methyl-methylene)-xylite 100 89 5-O-(2,4-Dichlorobenzyl)-1,2::3,4-bis-O-(methyl-propyl-methylene)-xylite 100 89 5-O-(2-Methylbenzyl)-1,2:3,4-bis-O-(methyl-propyl-methylene)-xylite 80 17 5-O-(2,6-Dichlorobenzyl-1,2:3,4-bls-O-(dlethyol-methylene)-xylite 100 171 5-O-(2-Methylbenzyl-1 ,2 :3,4-bis-0-(diethyl-methylene)-xylite 83 186 5-O-(2-Chlorobenzyl)-1,2:3,4-bis-O-(diethyl-methylene)-xylite 100 114 5-O-(2,4-Dichlorobenzyl)-1,2:3,4-bis-O-(methyl-methylene)-xylite 83 143 Example 6 Increased chlorophyll content of soya bean leaves In a series of tests carried out in a greenhouse, approximately 1 week old soya bean plants were treated with the compounds of the present invention listed in the Table below, in each case in the form of an aqueous emulsion. The concentration in each case, when converted, was approximately 0.8 kg of active substance per 500 litres of spray liquor.

After cultivating the plants for 7 weeks, leaf discs having a diameter of 1.7 cm were stamped out of the fifth leaf to develop (that is the 3rd true leaf). The chlorophyll was then extracted from the discs by means of ethanol. The amount of chlorophyll in the extract was determined photometrically at 665 nm.

In the Table the percentage chlorophyll a-content is expressed in comparison with the control for the individual treatments. An increased content is indicated by values greater than 100%.

Chlorophyll content as Compound of the invention a % of the control 5-0-(2,6-Dichlorobenzyl) 1,2 :3,4-bis-0-isopropylidene-xylite 290 5-0-(2,6-Dichlorobenzyl- 1,2 :3,4-bis-0-(ethyl-methyl-methylene)-xylite 262 5-O-(2,4-Dichlorobenzyl)-1 2 :3,4-bis-O(ethyl-methyl-methylene)-xyIite 1 54 5-O-(2-Chlorobenzyl- 1,2 :3,4-bis-O-(ethyl-mathyl-mathylena)-xylite 126 5-0-(2,6-Dichlorobenzyl)- 1,2 ::3,4-bis-O-(methyl-propyl-methylene)-xylite 1 74 Control Example 7 Influencing growth in cucumbers, French beans and soya beans In a series of tests cucumbers, French beans and soya beans are sprayed at two different stages of their development with the compounds of the present invention listed in the Table below; in each case an amount of 1 kg of emulsified active substance per 500 litres of spray liquor was used. Spraying took place 3 and 8 days, respectively, after sowing. Three weeks layer the average length of the plant, the number of internodes and the number of flower buds per plant were determined.

The following Table shows the results. The percentages given were produced by comparing the results with the control.

From these figures it can be seen that the compounds mentioned lead to a retardation of growth (length < 1 00) with the number of internodes often remaining almost the same. Furthermore, in the case of the French beans the number of flower buds was increased ( > 100) in the tests.

Spraying (No. of No. of Compound of the days after inter- Flower invention Plants sowing) Length nodes buds 5-0-(2,4-Dichlorobenzyl)-1,2:3,4-bis-0- Cucumber 3 83 93 isopropylidene-xylite 8 50 93 French beans 3 82 100 130 8 76 90 171 Soya beans 3 88 109 8 83 100 5-0-(2,6-Dichlorobenzyl)-1,2:3,4-bis-0- Cucumber 3 133 111 isopropylidene-xylite 8 60 80 French beans 3 52 92 110 8 65 117 257 Soya beans 3 82 88 8 76 78 Example 8 Growth regulation in soya beans-branching In a series of tests soya bean seeds were treated with the compounds of the present invention listed in the Table below, formulated in powder form, using amounts of 25 and 250 mg, respectively, of active substance per 100 kg of seed.Groups of 7 treated seeds each were sown in culture dishes with 500 ml of soil. After 5 weeks' cultivation in a greenhouse, the growth and morphological peculiarities of the plants were assessed.

The results are listed in the following Table. The average values per plant are given in the Table.

It is clear that the branching of the plants is considerably promoted by the application of the active substances indicated. This effect manifests itself, for example, in the lengths of the branching from the cotyledon axils. The number of internodes per plant can also be affected.

Length of branching Length of Dose from cotyle remaining Length of Compound of the (mg/100 kg don axils branching plants Number of invention of seeds incm. incm. incm. internodes 5-0-(2,4-Dichlorobenzyl)- 25 1.8 1.44 28 .8 1,2 :3,4-bis-0-isopropyl idene-xylite 250 2.0 1.7 26 5 5-0-(2,6-Dichlorobenzyl)- 25 5.1 2.4 23 3.7 1,2 ::3,4-bis-O-isopropyl idene-xylite 250 2.1 2.0 16 1.7 Control - 1.6 34 6.2 Example 9 Growth-regulating effects in soya beans-accelerated development of the generative phase In a series of tests soya beans were grown in culture dishes under greenhouse conditions. Two weeks after sowing, the active substances listed in the Table below, in an emlusified form, were sprayed onto the plants in the varying amounts shown in the Table. Seven weeks after sowing, the length of the plants, the number of flowers and flower buds, and also the number of pods and embryo pods were determined.

In the following Table the results of these tests are given in the form of percentages, in relation to the control.

The results show that in addition to the growth retardation (length < 100) and promotion of branching ( > 100) already described in earlier Examples, the generative phase is influenced by the first two compounds listed in the Table, that is compounds of the present invention. This is verified by the increased number of pods and embryo pods.

The plants bloomed earlier and, at the time that the evalution was carried out, they were at a further stage of development than the control. The substance used for comparison was phytoxic and displayed a considerably reduced growth-regulating effect Dose (g of active Flowers Compound of the substance/ and flower Embryo Pods invention hectares Length buds pods (2 cm) Branching 5-O-(2,4-Dichlorobenzyl 1,2:3,4-bis-0-isopropyl- 1000 100 115 134 143 127 idene-xylite 5-0-(2,6-Dichlorobenzyl/.

1,2:3,4-bis-0-isopropyl- 100 70 36 159 150 180 idene-xylite Comparison agent Thiiodobenzoic acid 70 58 111 62 0 190 7 42 93 21 0 136 Example 10 Growth-regulating effects in soya beans In a series of tests soya beans were cultivated under greenhouse conditions. A spray treatment was carried out before emergence and after emergence, respectively, with the active substances listed in the Table below, in an emulsified form. Six weeks after sowing, the number of branchings per plant was determined.

The results are given in the following Table.

The results show that the growth-regulating action of the compound of the present invention is superior to that of the agent used for comparison.

Dose (kg active Branchings per plant substance/ Before After Compound of the invention hectare) emergence emergence 5-0-(2,6-Dichlorobenzyl) 1,2:3.4-bis-O-isopropyl- 1 4 0.5 idene-xylite Comparison agent 2,3;4,6-Di-O-isopropylidene- 2.5 0 0.2 2-ketogulonic acid/sodium salt 5 0 0.2 Control O 0 Example 11 Morphological effect and increase in chlorophyll content in soya beans In a series of tests soya beans were subjected to a spray treatment after their emergence with the active substances listed in the Table below. using in each case an amount of 0.8 kg of active substance per hectare.

Three weeks after the spraying, the deformation of the leaves, the leaf position and the branching were determined and graded according to the following scale, depending on the degree of the symptoms: O=no effect . . 4=very strongly pronounced morphogenetic effect.

At the same time, leaf discs were stamped out of the 3rd true leaf of each plant. The chlorophyll was extracted from these leaf discs and the chlorophyll a-content was determined photometrically.

In the Table the gradings for the morphological effect and the increase in the chlorophyll content are given in comparison with the control.

The results show that at the spray concentration used, the growth-regulating effect of the compounds of the present invention is considerably more strongly pronounced that that of the substance used for comparison.

Morpho- Increase logical in chlorophyll effect a-content Compound of the invention grading as a 5-O-(2,6-Dichlorobenzyl-1,2:3,4-bls-O (benzyl-methyl-methylene)-xylite 2 25 5-0-(2,6-Dich lorobenzyl)- 1,2 :3,4-bis-0- (butyl-methyl-methylene)-xylite 3 33 5-0-(2,6-Dichlorobenzyl)-l ,2:3,4-bis-0- (1,1 -tetramethylene-methylene)-xylite 4 31 5-0-(2,4-Dichlorobenzyl)- 1,2 :3,4-bis-0- [(2-phenylethyl)-methyl-methylene]-xylite 0 12 5-0-(2,4-Dichlorobenzyl)- 1,2 ;3,4-bis-0- (methyl-methylene)-xylite 0 17 5-0-(2,6-Dichlorobenzyl)- 1,2 :3,4-bis-0- [(2-phenylethyl)-methyl-methylene]-xylite 2 14 5-0-(2,6-Dichlorobenzyl)-l : :3,4-bis-0- (4-chlorophenyl-methylene)-xylite 3 19 5-0-(2,6-Dichlorobenzyl)-1,2;3,4- (4-chlorophenyl-methylene)-xylite 0 16 5-0-(2,6-Dichlorobenzyl)- 1,2 :3,4-bis-O- (methyl-methylene)-xylite 1 5 5-0-(2,6-Dich lorobenzyl)- 1,2 :3,4-bis-0- (chloromethyl-methylene)-xylite 1 12 5-0-(2,6-Dichlorobenzyl)-1 .2:3,4- methylene-xylite 4 42 5-O-(2,4-Dichlorobenzyl)-1,2;3,4-bls-O (methyl-octyl-methylene)-xylite 0 25 5-0-(2,6-Dich lorobenzyl)- 1.2: :3 .4-bis-0- (methyl-octylmethylene)-xylite 5-O-(2,4-Dichlorobenzyl)-1,2;3,4-bis-O- 3 15 [(2,6-dichlorophenyl)-methylene]-xylite 0 8 Morpho- Increase logical in chlorophyll effect/ a-content Compound of the invention grading as a 5-O-(2-Chlorobenzyl)-1,2:3,4-bis-O [(2,6-dichlorophenyl)-methylene]-xylite 0 17 5-O-(2,6-Dichlorobenzyl)-1,2;3,4-bis-O methyl-phenoxymethyl-methylene)-xylite 1/2 20 Comparison agent 2,3 ;4,6-Di-O-isopropylidene-2-ketogulonic acid/sodium salt 0 6

Claims (124)

Claims

1. A xylite derivative of the general formulal

in which R1, R2, r3 and R4 each represents a hydrogen atom, an unsubstituted C1-C10-alkyl group, a C1-C10-alkyl group substituted by one or more substituents selected from halogen tom nd C1-C6alkoxy, phenoxy nd halogenophenoxy groups, an unsubstltuted aryl-C1-C3-alkyl group, an aryl-C1 C3-alkyl group substituted by one or more substituents selected from halogen atoms and C1-C-alkyl C1-C6-alkoxy, nitro and trifluoromethyl groups, a C3-C8-cycloaliphatic hydrocarbon group, an unsubstituted aromatic hydrocarbon group or an aromatic hydrocarbon group substituted by one or more substituents selected from halogen atoms and C1-C-aIkyl , C1-C6-alkoxy, nitro and trifluoromethyl grous, and R, and R2 together with the adjacent carbon atom may also represent a C3-C6-cycloallphatic hydrocarbon group and/or R3 and R4 together with the adjacent carbon atom may also represent a C3-C6-cycloaliphatic hydrocarbon group, R5 represents a hydrogen atom or a C1-C4-alkyl group, and Re represents an unsubstituted aromatic hydrocarbon group or an aromatic Hydrocarbon group substituted by one or more substituents selected from halogen atoms and C,Ce- alkyl, C1-C6-alkoxy, dioxymethylene, phenoxy, phenyl, nitro, cyano and trifluoromethyl groups.

2. A compound as claimed in claim 1, whereln R1, R2, R3 nd R4 each represents a hydrogen atom or a methyl, ethyl, propyl, isopropyl, n-butylm, sec, - butyl, tert. - butyl, 2,2-dlmethyl-1-propyl, n-pentyl, nheptyl, n-cotyl, n-decyl, chloromethyl, bromomethyl, fluoromethyl, dichloromethyl, trifluoromethyl, trichloromethyl, methoxymethyl, ethoxymethyl, phenoxymethyl, 4-chlorophenoxymethyl, chloroethyl, bromoethyl, 2-ethoxyethyl, 2-phenoxyethyl, cyclopropyl, cyclopentyl, cyclohexyl, benzyl, 2-phenylethyl, phenyl, 2-chlorophenyl, 3-chlorophenyl, 4-chlorophenyl, 3,4-dichlorophenyl, 4-methoxyphenyl, 4nitrophenyl or 2,4-dichlorophenyl group, R5 represents a hydrogen atom or a methyl group, and R6 represents a phenyl, 2-chlorophenyl, 3-chlorophenyl, 4-chlorophenyl, 2,6-dichlorophenyl, 2,4 dichlorophenyl, 3,4-dichlorophenyl, 2,4,6-trichlorophenyl, 4-bromophenyl, 2,4-dibromophenyl, 2,6- dibromophenyl, 2,4,6-tribromophenyl, 2-fluorophenyl, 3-fluorophenyl, 4-fluorophenyl, 2,4- difluorophenyl, 2-methylphenyl, 3-methylphenyl, 4-methylphenyl, 3,4-dimethylphenyl, 2- methoxyphenyl, 3-methoxyphenyl, 4-methoxyphenyl, 3,4-dioxymethylene-phenyl, 2-phenoxyphenyl, 3-phenoxyphenyl, 2-nitrophenyl, 3-nitrophenyl or 4-nitrophenyl group.

3.5-O-(2,4-Dichlorobenzyl)-1,2:3,4-bis-O-isopropylidene-xylite.

4.5-O-(2,6-Dichlorobenzyl)-1,2:3,4-bis-O-isospropylidene-xylite.

5.5-O-(2-Chlorobenzyl)-1,2:3,4-bis-O-isopropylidene-xylite.

6.5-O-(2,4-Dichlorobenzyl)-1,2:3,4-bis-O-(methyl-methylene)-xylite.

7.5-O-(4-Bromobenzyl)1,2:3,4-bis-O-isopropylidene-xylite.

8.5-O-(3,4-Dichlorobenzyl)-1,2;3,4-bis-O-isopropylidene-xylite.

9. 5-0-(4-Ch lorobenzyl)- 1,2 :3,4-bis-0-isopropyl idene-xylite

10. 5-O-(2-Chlorobenzyl)-1 ,2 :3,4-bis-0-isopropylidene-xylite

11. 5-O-(3-Chlorobenzyl)- 1,2 :3,4-bis-0-isopropylidene-xylite

12. 5-O-(2-Methylbenzyl)-1,2:3,4-bis-O-isopropylidene-xylite.

13. 5-O-(3-Methylbenzyl)-1,2:3,4-bis-O-isopropylidene-xylite.

14. 5-O-(4-Methylbenzyl)-1 ,2 :3,4-bis-0-isopropylidene-xylite.

15.5-O-(3,4-Dimethylbenzyl)-1,2:3,4-bis-O-isopropylidene-xylite.

16. 5-O-(2-Fluorobenzyl)- 1,2 :3,4-bis-0-isopropylidene-xylite.

1 7. uorobenzyi)- 1,2 :3,4-bis-0-isopropylidene-xylite.

18. 5-O-(4-Fluorobenzyl)-1 ,2 :3,4-bis-0-isopropylidene-xylite.

19. 5-O-(3-Trifluoromethylbenzyl)- 1,2 :3,4-bis-0-isopropylidene-xylite.

20. 5-O-Benzyl- 1,2 :3,4-bis-0-isop ropyl idene-xyl ite.

21. 5-O-(2,4-Dlchlorobenzyl)-1,2;3,4-bis-O-(diethylmethylene)-xylite.

22. 5-O-(2,6-Dichlorobenzyl)-1 ,2 :3,4-bis-0-(ethyl-methyl-methylene)-xyl ite.

23. 5-0-(2,4-Dichlorobenzyl)- 1,2 :3,4-bis-0-(ethyl-methyl-methylene)-xylite.

24. 5-O-(2-Ch lorobenzyl)- 1,2 :3,4-bis-0-(ethyl-methyl-methylene)-xylite.

25. 5-O-(2-Methylbenzyl)-1,2:3,4-bis-O-(ethyl-methyl-methylene)-xylite.

2 6. 5-0-(2,6-Dich lorob enzyl)- 1 ,2 :3,4-bis-0-(methyl-propyl-methylene)-xylite.

27. 5-O-(2,4-Dichlorobenzyl)-1,2:3,4-bis-O-(methyl-propyl-methylene)-xylite.

28. 5-O-(2-M ethylbenzyl)- 1,2 :3,4-bis-0-(methyl-propyl-methylene)-xylite.

29. 5-0-(2-Ch lorobenzyl)- 1,2 :3,4-bis-0-(methyl-propyl-m ethylene)-xylite.

30. 5-O-(2,6-Dich lorobenzyl)- 1.2 :3,4-bis-O-(diethyl-methylene)-xylite.

31. 5-O-(2-Methylbenzyl)- 1,2 :3,4-bis-0-(diethyl-methylene)-xylite.

32. 5-O-(2-Chlorobenzyl)-1 ,2 :3,4-bis-0-(diethyl-methylene)-xylite.

33. 5-0-(2-Methylbenzyl)- 1.2 :3,4-bis-O-(benzyl-m ethyl-methylene)-xylite.

34.5-O-(2-Chlorobenzyl)-1,2:3,4-bis-O-(benzyl-methyl-methylene)-xyllte.

35. 5-0-(2,4-Dichiorobenzyl)-l ,2 :3,4-bis-0-(benzyl-methyl-methylene)-xylite.

3 6. 5-0-(2,6-Dich lorobenzyl)- 1,2 :3,4-bis-O-(benzyl-m ethyl-methylene)-xylite.

37.5-O-(2-Methylbenzyl)-1,2,:3,4-bis-O-(butyl-methyl-methylene)-xylite.

38. 5-0-(2-Ch lorobenzyl)- 1,2 3,4-bis-O-(1,1 -tetra-methylene-methylene)-xylite.

39. 5-0-(2,4-Dichlorobenzyl)- 1,2:3,4-bis-O-(1,1 -tetra-methylene-methylene)-xylite.

40. 5-0-(2-Chlorobenzyl)- 1,2 :3,4-bis-0-(butyl-m ethyl-methylene)-xylite.

41. 5-0-(2,4-Dich lorobenzyl)- 1,2 :3,4-bis-0-(butyl-methyl-methylene)-xylite.

42. 5-O-(2-Methylbenzyl)-1 ,2;3,4-bis-0-(1,1 -tetramethylenemethylene)-xylite

43. 5-0-(2,6-Dichlorobenzyl)- 1,2 :3,4-bis-0-(butyl-methyl-methylene)-xylite.

44.5-O-(2,6-Dichlorobenzyl)-1,2:3,4-bis-O-(1,1-tetramethylene-methylene)-xylite.

45. 5-O-(2-Chlorobenzyl)- 1,2 :3,4-bis-O-[2-phenylethyl)-methyl-methylene]-xyllte.

46. 5-0-(2,4-Dichlorobenzyl)- 1 2 :3,4-bis-O-[(2-phenyl-ethyl)-methyl-methylene]-xylite

47. 5-0-(2,4-Dich lorobenzyl)- 1,2 :3,4-bis-0-(methyl-methylene)-xylite.

48. 5-O-(4-Phenylbenzyl)- 1,2 :3,4-bis-0-isopropylidene-xylite.

49. 5-O-(4-Cyanobenzyl)- 1,2 :3,4-bis-0-isopropylidene-xylite.

50. 5-0-(2,6-Dichlorobenzyl)- 1,2 :3,4-bis-O-[(2-phenyl-ethyl)-methyl-methylene]-xylite.

51. 5-O-(2-M ethylbenzyl)-1 ,2 :3,4-bis-O-[(2-phenyl-ethyl)-methyl-methylene,j-xylite.

52. 5-0-(2,6-Dichlorobenzyl)-1,2:3,4-bis-0-(4-chloro-phenyl-methylene)-xylite.

53. 5-O-(2-Chlorobenzyl)-1 ,2 :3,4-bis-0-(phenyl-methylene)-xylite.

54. 5-O-(2,4-Dichlorobenzyl)-1,2:3,4-bis-O-(4-chlorophenyl-methylene)-xylite.

55. 5-O-(2-Methylbenzyl)-1,2:3,4-bis-O-(4-chlorophenyl-methylene)-xylite.

56. 5-0-(2 ,8-Dichlorobenzyl)- 1,2 :3,4-bis-0-(phenyl-m ethylene)-xylite.

57. 5-0-(2,6-Dichlorobenzyl)- 1,2 :3,4-bis-O-(methyl-methylene)-xylite.

58. 5-0-(2-Methylbenzyl)- 1,2 :3,4-bis-O-(methyl-methylene)-xylite.

59. 5-0-(2-Chlorobenzyl)- ,2 :3,4-bis-O-(methyl-methylene)-xylite.

60. 5-0-(2,6-Dich lorobe nzyl)- 1 ,2 :3,4-bis-0-(ch lorom ethyl-m ethylene)-xyl ite.

61. 5-O-(2,4-Dichlorobenzyl)-1,2:3,4-bis-O-(chloromethyl-methylenen)-xylite.

62. 5-0-(2-M ethylbenzyl)- 1,2 :3,4-bis-O-(chloromethyl-methylene)-xylite.

63. 5-O-(2-Chlorobenzyl)-1,2:3,4-bis-O-(chloromethyl-methylene)-xylite.

64. 5-O-(2,6-Dichlorobenzyl)-1,2:3,4-bis-O-methylene-xylite.

65. 5-0-(2,4-Dichlorobenzyl)-l ,2 :3,4-bis-0-methylene-xylite.

66. 5-O-(2-Methylbonzyl)-1,2:3,4-bis-O-methylene-xylte.

67. 5-O-(2,4-Dichlorobenzyl)-1,2:3,4-bis-O-(methyl-octyl-methylene)-xylite.

68. 5-O-(2,6-Dichlorobenzyl-1,2:3,4-bis-O-(methyl-octyl-methylene)-xylite.

69. 5-0-(2-M ethylbenzyl)-l ,2 :3,4-bis-O-(methyl-octyl-methylene)-xylite.

70. 5-O-(2-Chlorobenzyl)-1 ,2 :3,4-bis-O-(methyl-octyl-methylene)-xylite.

71. 5-0-(2,4-Dichlorobenzyl)- 1,2 ;3,4-bis-O-(phenyl-methylene0-xylite.

72. 5-O-(2-Methylbenzyl)-1,2:3,4-bis-O-(phenyl-methylene) xylite.

73. 5-O-(2,4-Dichlorobenzyl)-1,2:3,4-bis-O-[(2,6-dichlorophenyl)-methylene)-xylite.

74. 5-O-(2-Methylbenzyl)-1,2:3,4-bis-O-[(2,6-dichlorophenyl)-methylene]-xylite.

75. 5-0-(2-Ch lorobenzyl)-l ,2 :3 ,4-bis-0-[(2,6-d ichlorophenyl)-m ethylene]-xyl ite.

76. 5-0-(2,6-Dichlorobenzyl)- 1,2 :3,4-bis-O-[(2,6-dichlorophenyl)-methylene]-xylite,

77. 5-0-(2,4,6-Tribromobenzyl)- 1,2 :3,4-bis-0-isopropylidene-xylite.

78. 5-0-(1 -Phenylethyl)-1,2 :3,4-bis-O-isopropylidene-xylite.

79. 5-0-[1 -(2,4-Dichlorophenyl)-ethyl]- 1,2 :3,4-bis-0-isopropylidene-xylite.

80. 5-0-[1 -(2,6-Dichlorophenyl)-ethyl]- 1,2:3,4-bis-O-isospropylidene-xyslite.

81. 5-O-(2,6-Dlchlorobenzyl)-1,2:3,4-bis-O-(methyl-phenoxymethyl-methylene)-xylite.

82. 5-0-(2,4-Dich lorobenzyl)-l ,2 :3,4-bis-0-(m ethyl-p henoxymethyl-methylene)-xyl ite.

83. A process for the manufacture of a compound of the general formula I given in claim 1, in which R1, R2, R3, R4, R5 and R6 have the meanings given in Claim 1, wherein A) a compound of the general formula II

is reacted with a compound of the general formula Ill

in the presence of an acid-binding agent, Rj, R2, R3, R4, R5 and R6 having the meanings given above and one of the symbols X and Y representing a halogen atom and the other symbol representing an -OH group, or B) a compound of the general formula II is reacted with a compound of the general formula II, R1, R2,R3, R4, R5 and Re having the meanings given above and one of the symbols X and Y representing a halogen atom and the other symbol representing an -OZ group, in which Z represents an alkali metal atom or a monovalent alkaline earth metal equivalent, or C) a compound of the general formula IV

in which R5 and Re have the meanings given above, is reacted a) with compounds of the general formulae V and VI

in which R1, R2, R3a and R4 have the meanings given above, in the presence of an acid catalyst and/or a dehydrating agent, or b) with compounds of the general formulae VII and VIII

in which Rt, R2, R3 and R4 have the meanings given above and R7, R8, R9 and R10 each represents a C1- C4-alkyl group, in the presence of an acid catalyst.

84. A process as claimed in claim 83, wherein the halogen atom is a chlorine or bromine atom.

85. A process as claimed in claim 83 or 84, wherein the alkali metal atom is a sodium. potassium or lithium atom.

86. A process as claimed in claim 83, conducted substantially as described herein.

87. A process as claimed in claim 83, conducted substantially as described in any one of Example 1 to 4 herein.

88. A preparation for regulating the growth of plants, which comprises at least one compound of the general formula I given in claim 1, in which R1, R2, R3, R4, Rs and Re have the meanings given in claim 1, in admixture or conjunction with a suitable carrier.

89. A preparation as claimed in claim 88, wherein the compound of the general formula I is a compound as claimed in claim 2.

90. A preparation as claimed in claim 88, wherein the compound of the general formula I is the compound claimed in any one of claims 3 to 82.

91. A preparation as claimed in any one of clajms 88 to 90, which is in the form of a powder, a strewable preparation, granules, a solution, an emulsion or a suspension.

92. A preparation as claimed in any of claims 88 to 91, containing a single compound of the general formula I.

93. A preparation as claimed in any one of claims 88 to 91, containing two or more compounds of the general formula I.

94. A preparation as claimed in any one of claims 88 to 93, which also contains one or more active substances selected from defoliants, plant-protecting agents, pesticides and herbicides other than compounds of the general formula

95. A preparation as claimed in any one of claims 88 to 94, wherein the total amount present of active substance or substances is approximately 10 to 80% by weight.

96. A preparation as claimed in any one of claims 88 to 95, containing one or more surfaceactive agents in a total amount of up to 20% by weight.

97. Any one of the preparations as claimed in claim 88 and substantially as described in Table I herein.

98. Any one of the preparations as claimed in claim 88 and substantially as described in Example 5, 6 and 7 herein.

99. A method of regulating the growth of a living plant. wherein the living plant and/or the area in the vicinity of the living plant is/are treated with a compound of the general formula I given in claim 1, in which R1. R2. R3, R4. R5amd Re have the meanings given in claim 1.

1 00. A method as claimed in claim 99, wherein the treatment is carried out with a compound as claimed in claim 2.

101. A method as claimed in claim 99, wherein the treatment is carried out with the compound claimed in any one of claims 3 to 82.

102. A method as claimed in claim 99, wherein the treatment is carried out with a preparation as claimed in any one of claims 88 to 98.

103. A method as claimed in any one of claims 99 to 102, wherein a single compound of the general formula I is used for the treatment in an amount within the range of from 0.005 to 5 kg per hectare.

104. A method as claimed in any one of claims 99 to 102, wherein two or more compounds of the general formula I are used for the treatment in a total amount within the range of from 0.005 to 5 kg per hectare.

105. A method as claimed in any one of claims 99 to 104, wherein the plant is a leguminous plant.

106. A method as claimed in claim 105, wherein the leguminous plant is a soya bean plant.

107. A method as claimed in claim 99, conducted substantially as described in any one of Example 6, 7, 9, 10 and 11 herein.

108. A method of regulating the growth of plants in an area of land, wherein the area is treated with a compound of the general formula I given in claim 1, in which R1. R2, R3. R4. R5 and Re have the meanings given in claim 1.

109. A method as claimed in claim 108, wherein the treatment is carried out with a compound as claimed in claim 2.

110. A method as claimed in claim 108, wherein the treatment is carried out with the compound claimed in any one of claims 3 to 82.

111. A method as claimed in claim 108, wherein the treatment is carried out with a preparation as claimed in any one of claims 88 to 98.

112. A method as claimed in any one of claims 108 to 111, wherein a single compound of the general formula I is used for the treatment in an amount within the range of from 0.005 to 5 kg per hectare.

113. A method as claimed in any one of claims 108 to 111, wherein two or more compounds of the general formula I are used for the treatment in a total amount within the range of from 0.005 to 5 kg per hectare.

114. A method as claimed in any one of claims 108 to 113, wherein the area of land is a crop area.

11 5. A method as claimed in claim 114, wherein the crop is a leguminous crop.

11 6. A method as claimed in claim 11 5, wherein the leguminous crop is a soya bean crop.

117. A method of dressing seeds, wherein the seeds are treated with a compound of the general formula I given in claim 1, in which R1, R2, R3, R4, R5 and Re have the meanings given in claim 1.

11 8. A method as claimed in claim 11 7, wherein the treatment is carried out ith a compound as claimed in claim 2.

11 9. A method as claimed in claim 11 7, wherein the treatment is carried out with the compound claimed in any one of claims 3 to 82.

120. A method as claimed in claim 11 7, wherein the treatment is carried out with a preparation as claimed in any one of claims 88 to 98.

121. A method as claimed in claim 11 7, conducted substantially as described in Example 5 or 8 herein.

122. A pack which comprises a compound of the general formula I given in claim 1, in which R1, R2, R3, R4, R5 and Re have the meanings given in claim 1. together with instructions for its use in regulating the growth of living plants.

123. A pack as claimed in claim 122, wherein the compound of the general formula I is a compound as claimed in claim 2.

124. A pack as claimed in claim 122, wherein the compound of the general formula I is the compound claimed in any one of claims 3 to 82.