GB2038305A

GB2038305A - Plant growth regulating compositions

Info

Publication number: GB2038305A
Application number: GB7935559A
Authority: GB
Original assignee: Duphar International Research BV
Current assignee: Duphar International Research BV
Priority date: 1978-10-16
Filing date: 1979-10-12
Publication date: 1980-07-23
Also published as: GR66669B; EG13925A; IT7926481A0; BE879425A; AU5175279A; DE2941658A1; ZA795206B; JPS55113705A; IL58444A0; TR20218A; FR2438424A1; IT1162591B; DK432079A; NL7810350A

Abstract

Plant growth regulating compositions comprising N-aryl iminohexahydropyrimidine and N-aryl iminohexahydroimidazoline compounds or salts and complexes thereof with a solid or a liquid inert carrier, said compounds comprising known and novel compounds of the formula <IMAGE> in which formula n is 0 or R1 is a substituent in the 4-position, R2 is a substituent in the 3-position of a phenyl radical, R3, R4 and R5 are equal or different each representing a hydrogen or an alkyl group whilst R4 may also represent an alkanoyl group and in which novel compounds are represented by the above formula when R3, R4 and R5 are each a hydrogen atom, n is 0 or 1 and the R1 R2 @ substituent is represented by <IMAGE> wherein R1<''> is an n-propyl, an iso propyl, an n-propylthio or a tert. butyl group and R2<'> is hydrogen or a chlorine atom and <IMAGE> wherein m is 1 or 2, R6 is H, Cl or CH3 and R2 is H or a chlorine atom.

Description

SPECIFICATION Plant growth-regulating compositions The invention relates to a composition for use in the regulation of plant growth and to a method of preparing said composition. The invention particularly relates to the use of this composition in agriculture and horticulture. The invention also relates to novel hexahydropyrimidine - and imidazolidine compounds.

In agriculture and horticulture it is often desired to control the growth of trees, shrubs or non-woody plants, or parts thereof. It may be necessary, for example, to inhibit the growth of plants, such as fruit trees, hedge shrubs or lawn grass. It may also be advantageous to influence the growth of parts of plants, for example, by inhibiting the growth of the terminal buds of sugar cane so that the stems can develop better and the yield of sugar is increased. It may also be of importance to inhibit or suppress the development of suckers, in particular in those plants in which the formation of suckers frequently occurs, for example, in various ornamental plants, in tomato plants and in tobacco plants. Said suckers consume much nutrient which consequently does not favour the development of other parts of the plants, for example, the leaves, flowers and fruits.In the case of tobacco plants it is frequently necessary to inhibit suckers to a considerable extent because the size and quality of the tobacco plant or plants is very adversely influenced by the development of suckers and in practice for large plots containing many tobacco plants the manual removal of the suckers is both time-consuming and expensive.

It has now been found that compounds of the general formula

wherein R1 is a halogen-substituted or non-halogen-substituted alkyl-, alkenyl- alkoxy-, alkenyloxy-, alkylthio-, alkenylthio, alkoxyalkyl- or alkylthioalkyl group having 3 to 12 carbon atoms, a mono-, bi- or tricyclo alkyl group having 3 to 12 carbon atoms, a phenyl-, phenoxy-, phenylthio-, phenylalkyl-, phenylalkoxy- or phenylalkylthio group having 6 to 10 carbon atoms, which phenyl group or the phenyl group of which is substituted, if desired, with halogen or with alkyl, alkoxy or alkylthio, which alkyl-, alkoxyor alkylthio groups have 1 to 6 carbon atoms and may be halogenated, or a furylalkyl- orthienylalkyl group having 5 to 8 carbon atoms, R2 is a hydrogen atom or a halogen atom, or wherein R1 and R2 together represent a trimethylene or tetramethylene group, P3 and R4 are equal or different and represent a hydrogen atom or an akyl group or alkanoyl group having 1 to 4 carbon atoms, P5 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and n isO or 1, or salts and complexes of these compounds have a plant growth-regulating activity.

According to the invention there is provided a composition for use in the regulating of plant growth which comprises the aforesaid compound as represented by the general formula or a salt or complex thereof and a solid or liquid inert carrier, if desired, with growth regulators, pesticidal compounds, fertilizers and/or auxiliary substances.

In one embodiment compositions which are particularly active when used for regulating plant growth comprise a compound of the general formula

wherein R', is an n-alkyl group having 5 to 9 carbon atoms or a phenylethyl group, or salts or complexes thereof.

Examples of suitable compositions contain one or more of the following compounds which are very active: (1) 2-(4-n-pentyphenyl)imino-hexahydropyrimidine, (2) 2-(4-n-hexylphenyl)imino-hexahydropyrimidine, (3) 2-(4-n-heptylphenyl)imino-hexahydropyrimidine, (4) 2-(4-n-octyl phenyl)imino-hexahydropyrimidine, (5) 2-(4-n-nonylphenyl)imino-hexahydropyrimidine and (6) 2-[4-(2-phenylethyl)phenyl]imino-hexahydropyrimidine.

Other compounds which are also suitable for use in the compositions according to the invention are: (7) 2-(4-n-hexylthiophenyl )imino-hexahydropyrimidine, (8) 2-(4-n-octyloxyphenyl)-imino-hexahydropyrimidine, (9) 1 -methyl-2-(4-n-hexylphenyl)imino-hexahydropyrimidine, (10) 2-(4-n-hexylthiomethylphenyl)im ino-hexahydropyrimidine, (11) 2-[4-42-(4-methylphenyl)ethyl}phenyl]imino-hexahydropyrimidine, (12) 2-(4-sec.butylthiomethylphenyl)imino-hexahydropyrimidine, (13) 2-(4-isopentylthiophenyl)imino-hexahydropyrimidine, (14) 1 -methyl-2-[4-(1 -methyl heptylthio)phenyl]iminohexahydropyrimidine, (15) 2-[4-(1 -methyl butyl )phenyl] imino-hexahydropyri midine, (16) 2-[4-(1 -methylbutylthio)phenyl]imino-hexahydropyrimidine, (17) 2-(4-n-hexyloxyphenyl)imino-hexahydropyrimidine, (18) 2-[4-(1 -methylheptylthio)phenyl]imino-hexahydropyrimidine, (19) 2-(4-n-octylphenyl)imino-4-methyl-hexahydropyrimidine, (20) 2-[4-(4.chlorobenzyloxy)phenyl]imino-hexahydropyrimidine, (21) 2-(4-n-octylphenyl)imino-hexhydropyrimidine acetate, (22) 2-(4-cyclohexylphenyl)imino-hexahydropyrimidine, (23) 2-(4-benzylphenyl )imino-hexahydropyrimidine, (24) 2-[4-(2-chloroailylthio)phenyl]imino-hexahydropyrimidine, (25) 2-(3-chloro-4-n-propylthiophenyl)imino-hexahydropyrimidine, (26) 2-(4-n-octylthiophenyl)imino-hexahydropyrimidine, (27) 2-(4-n-decylthiophenyl)imino-hexahydropyrimidine, (28) 2-[4-(4-methylphenylthio)phenyl]imino-hexahydropyrimidine, (29) 2-[4-(4-chlorophenylthio)phenyl]imino-hexahydropyrimidine, (30) 2-(4-n-dodecyloxyphenyl)imino-hexahydropyrimidine, (31) 2-(4-phenoxyphenyl)imino-hexahydropyrimidine, (32) 2-[4-(4-methylphenoxy)phenyl]imino-hexahydropyrimidine, (33) 2-[4-(4-chlorophenoxy)phenyl]imino-hexahydropyrimidine, (34) 2-(3-chloro-4-phenoxyphenyl)imino-hexahydropyrimidine, (35) 1 1,3-diethyl-2-(4-n-butyl phenyl )im i no-hexahydropyrimidine, (36) 1 ,3-diacetyl-2-(4-cyclohexylphenyl)imino-hexa hydropyrimidine, (37) 2-(4-n-heptylphenyl)imino-imidazolidine, (38) 2-(4-n-hexylphenyl)imino-imidazolidine, (39) 2-(4-n-octylphenyl)imino-imidazolidine, (40) 2-[4-(2-chloroallylthio)phenyl]imino-imidazolidine, (41) 2-[4-(1 -methylheptylthio)phenyl]imino-imidazolidine, (42) 2-[4-(2-methyl phenoxy)phenyl]imino-hexa hydropyrimidi ne, (43) 2-[4-(3,5-dimethyl phenoxy)phenyl]imino-hexahydropyrimidine, (44) 2-(4-cyclohexylphenyl)imino-hexahydropyrimidine cinnamate, (45) 2-(4-n-propylphenyl)imino-hexahydropyrimidine, (46) 2-(4-cyclohexylphenyl)imino-hexahydropyrimidine p-dodecylbenzenesulfonate, (47) 2-(4-n-octylphenyl)imino-hexahydropyrimidine p-dodecylbenzenesulfonate, (48) 2-(4-n-butylphenyl)imino-hexahydropyrimidine p-dodecylbenzenesu lfonate, (49) 2-(4-cyclohexylphenyl )imino-hexahydropyrimidine acetate, (50) 2-(4-n-octylphenyl)imino-hexahydropyrimidine zinc chloride complex, (51) 2-(4-cyclohexylphenyl )imino-hexahydropyrimidine zinc acetate complex, (52) 2-(4-cyclohexylphenyl)imino-hexahydropyrimidine cupriacetate complex, (53) 2-(4-cyclohexylphenyl )imino-hexahydropyrimidine phosphorous acid ethyl ester, (54) 2-(4-cyclohexylphenyl)imino-hexahydropyrimidine phosphorous acid n-butyl ester, (55) 2-(4-tert.-butylphenyl )imino-hexahydropyrimidine, (56) 2-[4-(2,5-dimethylphenoxy)phenyl]imino-hexahydropyrimidine, (57) 2-(4-cyclohexylphenyl)imino-hexahydropyrimidine benzothiazole thiolate, (58) 2-(4-adamantyiphenyi)imino-hexahydropyrimidine, (59) 2-(3,4-tetramethylenephenyl)imino-hexahydropyrimidine, (60) 2-[4-12-(2-methylphenyl )ethylphenyl]imino-hexahydropyrimidine, (61) 2-[4-(2-furylethyl)phenyl]imino-hexahydropyrimidine, (62) 2-[4-(2-(4-isopropoxyphenyl )ethylphenyl]imi no-hexahydropyrimidine, (63) 2-[4-42-(4-chlorophenyl)ethyl}phenyl]imino-hexahydropyrimidine, (64) 2-[4-I2-(4-isopropyl phenyl )ethyl)phenyl]im ino-hexahydropyrimidine, (65) 2-(4-{2-(4-ethoxyphenyl)ethyl}phenyl)imino-hexahydrnpyrimidine, (66) 2-[4-{2-(2-n-butoxyphenyl)ethyl}phenyl]imino-hexahydropyrimidine, (67) 2-(4-isopropylphenyl)imino-hexahydropyrimidine,and (68) 2-(4-n-butylphenyl)imino-hexahydropyrimidine.

Most of the above-mentioned compounds are described in the non-prepublished Netherlands Patent Application 7711390 in the name of Applicants; these compounds are stated as having a fungicidal activity.

A number of the above-mentioned compounds is novel. Therefore, the invention also relates to the following novel compounds: 2-[4-(2-chloroallylthio)phenyl]imino-hexahydropyrimidine, m.p. 104"C; 2-(3-chloro-4-n-propylthiophenyl)imino-hexahydropyrimidine, m.p. 123"C; 2-(4-phenoxyphenyl)imino-hexahydropyrimidine, m.p. 181"C; 2-[4-(4-methylphenoxy)phenyl]imino-hexahydropyrimidine, m.p. 129"C; 2-[4-(4-chlorophenoxy)phenyl]imino-hexahydropyrimidine, m.p. 153"C; 2-(3-chloro-4-phenoxyphenyl)imino-hexahydropyrimidine, oil; 1 ,3-diethyl-2-(4-n-butylphenyl )imino-hexahydropyrimidine, oil;; 2-[4-(2-chloroallylthio)phenyl]imino-imidazolidine, m.p. 90"C; 2-[4-(1-methylheptylthio)phenyl]imino-imidazolidine, oil; 2-[4-(2-methyl phenoxy)phenyl]imino-hexahydropyrimidine, m.p. 147"C; 2-[4-(3,5-dimethylphenoxy)phenyl]imino-hexahydropyrimidine m.p. 145 C; 2-(4 n-propylphenyi)imino-hexahydropyrimidine/ m.p. 110 C; 2-(4-n-octylphenyl)imino-hexahydropyrimidine p-dodecylbenzene sulfonate, oil; 2-(4-tert.-butylphenyl)imino-hexahydropyrimidine, m.p. 180"C; 2-[4-(2,5-dimethylphenoxy)phenyl]imino-hexahydropyrimidine, m.p. 148"C;; 2-(4-cyclohexylphenyl)imino-hexahydropyrimidine benzothiazole thiolate, m.p. 169"C; 2-(4-acamantylphenyl)imino-hexahydropyrimidine, m.p. 226"C; 2-[442-(2-n-butoxyphenyl)ethyl}phenyl]imino-hexahydropyrimidine, m.p. 110"C; and 2-(4-isopropylphenyl)imino-hexahydropyrimidine, m.p. 134"C.

The novel substances may be prepared according to the methods described in the above-mentioned Netherlands Patent Application 7711390.

According to the invention there is provided a method of preparing the compositions of the invention characterised in that a compound of the general formula as defined above is mixed with a solid carrier material or dissolved or dispersed in an inert liquid carrier material, if desired in combination with other growth regulators, pesticidal compounds, fertilizers and/or auxiliary substances, such as emulsifiers, wetting agents, dispersing agents and stabilizers.

Examples of compositions of the invention are aqueous solutions and dispersions, oily solutions and oily dispersions, solutions in organic solvents, pastes, dusting powders, dispersible powders, miscible oils, granules, pellets, invert emulsions, aerosol compositions and fumigating candles.

Dispersible powders, pastes and miscible oils are compositions in a concentric form which are diluted prior to or during use.

The invert emulsions and solutions in organic solvents are mainly used in air application, namely when large areas are treated with a comparatively small quantity of composition. The invert emulsion may be prepared shortly prior to or even during spraying in the spraying'apparatus by emulsifying water in an oily solution or an oily dispersion of the active substance. The solutions of the active substance in organic solvents may be provided with a material reducing phytotoxicity, for example, wool-fat, wool-fatty acid or wool-fatty alcohol.

By way of example, a few forms of composition will be described in detail hereinafter.

Granular compositions are prepared, for example, by dissolving the active substance in a solvent or by dispersing the active substance in a diluent and impregnating the resulting solution/suspension, if desired in the presence of a binder, on granular carrier material, for example, porous granules (for example, pumice and attaclay), mineral non-porous granules (sand or ground marlow) organic granules (for example, dried coffee-grounds, cut tobacco stems and ground corn cobs). A granular composition can also be manufactured by compressing the active substance together with powdered minerals in the presence of lubricants and binders and disintegrating the compressed product to the desired grain size and sieving it.

Granular compositions can be prepared in a different manner by mixing the active substance in powder form with powdered fillers and then glomulating the mixture with liquid to the desired particle size.

Dusting powders can be prepared by intimately mixing the active substance with an inert solid powdered carrier material, for example talc.

Dispersible powders are prepared by mixing 10 to 80 parts by weight of a solid inert carrier, for example, kaolin, domolite, gypsum, chalk, bentonite, attupulgite, colloidal SiO2 or mixtures of those and similar substances, with 10 to 80 parts by weight of the active substance, 1 to 5 parts by weight of a dispersing agent, for example, the lignin sulphonates or alkylnaphthalene sulphonates known for this purpose, preferably also 0.5 to 5 parts by weight of a wetting agent, for example, fatty alcohol sulphates, alkylaryl sulphonates, fatty acid condensation products, or polyoxyethylene compounds, and finally, if desired, other additives.

Forthe preparation of miscible oils, the active compound is dissolved in a suitable solvent which is preferably poorly water-miscible and one or more emulsifiers are added to this solution. Suitable solvents are, for example, higher alcohols, for example lauryl alcohol, decanol and octanol xylene, toluene, petroleum distillates which are rich in aromatics, for example solvent nahptha, distilled tar oil and mixtures of these liquids. As emulsifiers may be used, for example, polyoxyethylene compounds and/or alkyl aryl sulphonates. The concentration of the active compound in these miscible oils is not restricted to narrow limits and may vary, for example, between 2 and 50% by weight.

In addition to a miscible oil may be mentioned as a liquid and highly concentrated primary composition also a solution of the active substance in a readily water-miscible liquid, for example a glycol or glycol ether, to which solution a dispersing agent and possibly a surface-active substance has been added. Upon dilution with water shortly before or during spraying an aqueous dispersion of the active substance is obtained.

An aerosol composition according to the invention is obtained in the usual manner by incorporating the active substance, if desired in a solvent, in a volatile liquid to be used as a propellant gas, for example, a mixture of chlorofluoro derivatives of methane and ethane, a mixture of lower hydrocarbons, dimethyl ether or gases, for example, carbon dioxide, nitrogen and laughing gas (nitrous oxide N2O).

Fumigating candles or fumigating powders, i.e. compositions which while burning can develop a pesticidal smoke, are obtained by taking up the active substance in a combustible mixture which may comprise, for example, as a fuel, a sugar or a wood, preferably in a ground form, a substance to maintain combustion, for example, ammonium nitrate or potassium chlorate, and furthermore, a material to delay combustion, for example, kaolin, bentonite and/or colloidal silicic acid.

In addition to the above-mentioned ingredients, the agents according to the invention may also comprise other materials known for application in this type of agents.

For example, a lubricant, such as calcium stearate or magnesium stearate, may be added to a dispersible powder or a mixture to be granulated. "Adhesives", for example, polyvinyl alcohol cellulose derivatives or other colloidal material, such as casein, may also be added, for example, so as to improve the adhesion of the composition to the crop. Furthermore, a material may be added to delay the phytotoxicity of the active substance, carrier material or auxiliary material, such as wool-fat or wool fatty alcohol.

Known growth regulators and pesticidal compounds may also be incorporated in the compositions according to the invention. As a result of this, the activity spectrum of the composition is widened and synergism may occur. In addition, leaf fertilizers may be present. The following known growth controllers, herbicidal, fungicidal, nematidical, insecticidal, and acaricidal compounds are suitable for use in such a combination composition.

Growth regulators, for example: 1. higher alcohols, for example, octanol and decanol 2. lower esters of fatty acids; 3. generators of ethylene, for example, (2-chloroethyl) phosphonic acid and 2-chloroethyl-tris(2 methoxyethoxy)silane: 4. nitrodiphenyl ethers; 5. substituted dinitro anilines; 6. trifluoromethylsulphonylamino compounds; 7. piperidine derivatives; and furthermore maleic hydrazide; 2,3:4,6-di-0-isopropylidene-a-xylo-2-hexulo-furanosonic acid-sodium; N,N-dimethyl- amino succinic acid; a-cyclopropyl-4-methoxy-a-(pyrimidin-5-yl)benzyl alcohol: 2chloroethyltrimethyl ammonium; N,N-di(phosphonomethyl)glycine; 9-hydroxyfluorene-9-carboxylic acid (or ester); 2-chloro-9-hydroxyfluorene-9-carboxylic acid (or ester);N-1 -naphthylphthalaminic acid; and 2,3-dihydro-5,6-diphenyl-1 ,4-oxathiine; of mixtures of these compounds.

Herbicides, for example: S-propyl butylethylthiocarbamate; N-( 1 -ethylpropyl)-2,6-dinitro-3,4-xylidine; N,N-dimethyldiphenyl acetamide; 4-isopropyl-2,6-dinitro-N,N-dipropylaniline; and N,N-diethyl-2-(1-naphthalenyloxy) propanamide; or mixtures of these compounds.

Fungicides, for example: 1. organic tin compounds, for example, triphenyl tin hydroxide and triphenyl tin acetate; 2. alkylenebisdithiocarbamates, for example, zinc ethylenebisdithiocarbamate and manganese ethylenebisdithiocarbamate; 3. 1-acyl- or 1-carbamoyl-N-benzimidazole (-2) carbamates and 1,2-bis (3-alkoxycarbonyl-2thiureido)benzene, and furthermore 2,4-dinitro-6-(2-octylphenyl)crotonate, 1-[bis(dimethylamino)phosphoryli-3-phenyl-5-amino-1 ,2,4-triazole, N-trichloromethylthiophthalimide, N tricholoromethylthiotetrahydrophthalimide, N-(1 ,1 ,2,2-tetrachloroethylthio)-tetrahydrophthalimide, N dichlorofluoromethylthio-N-phenyl-N,N'-dimethylsulphamide, tetrachloroisophthalonitrile, 2-(4'thiazolyl)benzimidazole, 5-butyl-2-ethylamino-6-methylpyrimidine-4-yl-dimethylsulphamate,1-(4- chlorophenoxy)-3,3-dimethyl-1 (1 ,2,4-triazole-1 -yl)-2-butanone, a-(2-chlorophenyl-a-(4-chlorophenyl)-5- pyrimidine methanol, 1 -(isopropylcarbamoyl)-3-(3,5-dichlorophenyl)hydantoine, N-(1 ,1 2,2- tetrachloroethylthio)-4-cyclohexene-1 ,2-carboximide, N-trichloromethylmercapto-4-cyclohexene-1 ,2- dicarboximide, N-tridecyl-2,6-dimethylmorpholine and acylalanine, or mixtures of these compounds.

Nematicides, for example: 1. carbamates, for example, 2-dimethylamino-5,6-dimethylpyrimidin-4-yI dimethylcarbamate, 2isoproxyphenyl methylcarbamate, and 2,3-dihydro-2,2-dimethylbenzofuran-7-yl-methylcarbamate; 2. phosphorothioates, for example, ethyl S,S-dipropyl phosphorodithioate, 0,0-dialkyl 0-4-nitrophenyl phosphorothioate and 0,0-diethyl-0-4-methylsulfinylphenyl phosphorothioate; and furthermore 2-methyl-2 (methylthio)propionaldehyde 0-methylcarbamoyloxime and 1 ,3-dichloropropane; or mixtures of these compounds.

Insecticides including aphicides, for example: 1. organic chlorine compounds, for example, 6,7,8,9,1 0-hexachloro-1 ,5,5a,6,9,9a-hexahydro-6,9-methano- 2,4,3-benzo[e]-dioxathiepine 3-oxide; 2. carbamates, for example, 2-dimethylamino-5,6-dimethyl-pyrimidin-4-yl dimethyl carbamate, 1 -naphthyl methyl-carbamate, 2-isopropoxyphenyl methylcarbamate and 2,3-dihydro-2,2-dimethylbenzofuran-7-yl methyl carbamate; 3. di(m)ethylphosphates, for example,2-chloro-2-diethyl-carbamoyl-1-methylcinyl , 2- methoxycarbonyl-1 -methylvinyl ----,1-methyl-2-methylcarbamoylvinyl , -----,2-ch loro-1 -(2,4- dichlorophenyl)vinyl -----,2,2-dichlorovinyl -----, and 2-chloro-1-(2,4,5-trichlorophenyl)vinyl di (m)ethylphosphate; 4. 0,0-di(m)ethyl phosphorothioates, for example 0(S)-2-methylthio-ethyl -----, S-2-ethylsulfinylethyl -----, S-2-(1-methylcarbamoylethylthio)ethyl -----,0-4-bromo-2,5-dichlorophenyl -----,0-3,5,6-trichloro-2-pyridyl -----,0-2-isopropyl-6-methylpyrimidin-4-yl , 0-2-isopropyl-6-methylpyrimidin-4-yl , 0-4-methyl sulfinylphenyl -----, and 0.4-nitrophenyl 0,0- di(m)ethyl phosphorothioate; 5. 0,0-di(m)ethyl phosphorodithioates, for example, S-methylcarbamoyl-methyl -----, S-2-ethylthioethyl -----, , S-(3,4-dihydro-4-oxo-benzo [di - [1,2,3] -triazin-3-ylmethyl) -----, , S-1,2-di(ethoxycarbonyl)ethyl -----, S-6-chloro-2-oxobenzoxazolen-3-ylmethyl -----, and S-2,3-dihydro-5-methoxy-2-oxo-1 ,3,4-thiadiazol-3- ylmethyl 0,0-di(m)ethyl phosphorodithioate; 6.Phosphonates, for example, dimethyl 2,2,2-trichloro-1 -hydroxyethyl phosphonate; and furthermore 0-ethyl S,S-dipropyl phosphorodithioate; S-methyl N-(methylcarbamoyloxy) thioacetamidate; 0,S-dimethyl acetyl-phosphoramidathioate; and 0-ethyl-5-phenyl ethylphosphonodithioate; or mixtures of these compounds.

Acaricides, for example: 1. organic tin compounds, for example, tricyclohexyl tin hydroxide and di [tri-(2-methyl-2-phenylpropyl)tin] oxide; 2. organic halogen compounds, for example, isopropyl 4,4'-dibromobenzilate and 2,2,2-trichloro-1,1-di(4chlorophenyl) ethanol; and furthermore: 3-chloro-α-ethoxyimino-2,6-dimethoxy-benzyl benzoate and 0,0-dimethyl Smethylcarbamoylmethyl phosphorothioate; or mixtures of these compounds.

The dosage of the composition according to the invention desired for practical application will depend inter alia on the active substance chosen, the form of composition, the kind of crop to be treated, the state of the crop and the weather conditions. In general favourable results are obtained with a dose corresponding to 100-5000 g of the active substance per hectare. Said dosage may be provided in one time but may also be provided by spraying several times.

The invention will now be described in greater detail with reference to the ensuing specific examples.

Example I 2.5 g of alkylphenylpolyoxyethylene and 2.5 g of a mixture of an alkylphenylsulphonate and a polyoxyethylene compound were dissolved in 3 litres of acetone. This solution was used as a solvent for the active substances. The quantity by weight of active substance necessary for the desired concentration - see Table 1 - was dissolved in 2 ml of the above-mentioned solvent. Immediately before spraying, 18 ml of water were added to the solution thus obtained. If the active substance did not dissolve in the above-mentioned solvent, the compound was dispersed in the solvent after having been ground.

9 weeks old tobacco plants were sprayed in the hot house with the resulting compositions; 6 days before spraying the heads of the plants had been removed. Upon spraying the uppermost suckers were up to approximately 0.6 cm long. 3 plants were used per concentration of which only the suckers, the phyllopodium, and stem were sprayed.

Two weeks after spraying, the activity of the active substances was determined by finding out to what extent, if any, the development of the suckers had been inhibited. The results of this evaluation are recorded in Table 1, in which the following evaluation was used: - = no effect + = weak growth inhibition + = strong growth inhibition ++ = very strong effect, the suckers are dead TABLE I Evaluation of the conc. in sucker inhibiting active substance mg/l effect 2-(4-n-hexylthiophenyl)imino- 1000 + hexahydropyrimidine 750 + 500 + 250 + 1-methyl-2-(4-n-hexylphenyl)- 1000 + imino-hexahydropyrimidine 750 + 500 2-(4-n-hexylphenyl)imino- 1000 ++ hexahydropyrimidine 750 ++ 500 ++ 250 ++ 2-(4-n-heptylphenyl)imino- 1000 ++ hexahydropyrimidine 750 ++ 500 ++ 250 ++ 2-4-(2-phenylethyl)phenyl 1000 ++ imino-hexahydropyrimidine 750 ++ 500 ++ 250 ++ 2-(4-n-nonylphenyl)imino- 1000 ++ hexahydropyrimidine 750 ++ 500 ++ 250 + 2-(4-n-hexylthiomethylphenyl)- 1000 + imino-hexahydropyrimidine 750 + 500 2-[4-(2-(4-methylphenyl) 1000 + ethyl)-phenyl]imino- 750 + hexahydropyrimidine 500 + 250 2-(4-sec.butylthiomethylphenyl)- 1000 + imino-hexahydropyrimidine 750 + 500 2-(4-isopentylthiophenyl)imino- 1000 + hexahydropyrimidine 750 + 500 + 250 2-(4-n-pentylphenyl)imino- 1000 ++ hexahydropyrimidine 750 ++ 500 + 250 + 2-(4-n-hexyloxyphenyl)imino- 1000 + hexahydropyrimidine 750 + 500 + 250 2-(4-n-octylphenyl)imino- 1000 ++ hexahydropyrimidine 750 ++ 500 + 250 + 2-(4-n-octylphenyl)imino- 1000 ++ hexahydropyrimidine acetate 750 + 500 + 250 + 2-(4-n-octyloxyphenyl)imino- 1000 + hexahydropyrimidine 1-methyl-2-[4-(-methylheptyl)- 1000 + thiophenyl]iminohexahydropyrimidine TABLE I (cont.) Evaluation of the conc. in sucker inhibiting active substance mg!l effect 2-[4-(1 -methylbutyl)phenyl] 1000 + imino-hexahydropyrimidine 2-[4-(1 -methylbutyl)thiophenyl]- 1000 + imino-hexahydropyrimidine 2-[4-(1 -methylheptyl)thiophenyl]- 1000 + imino-hexahydropyrimidine 2-(4-n-octylphenyl)imino-4- 1000 + methyl-hexahydropyrimidine 2-[4-(4-chlorobenzyloxy)phenyl]- 1000 + imino-hexahydropyrimidine 2-[4-(4-methylphenoxy)phenyl] 1000 + imino-hexahydropyrimidine 2-[4-(4-chloro benzyloxy)phenyl] 1000 t imino-hexahydropyrimidine 2-(4-n-heptylphenyl)imino- 1000 + imidazoline 2-(3,4-tetramethylenephenyl) 1000 + imino-hexahydropyrimidine 2-[4-(2-chloroallylthio)phenyl] 1000 + imino-hexahydropyrimidine 2-[4-12-(2-methylphenyl)ethyl) 1000 ++ fenyl]imino-hexahydropyrimidine 2-[4-(2-furylethyl)phenyl] 1000 + imino-hexahydropyrimidine 2-[4-(2-(4-isopropoxyphenyl) 1000 ++ ethyl)phenyl]iminohexahydropyrimidine 2-[4-42-(4-chlorophenyl)ethylt 1000 + + phenyl]imino-hexahydropyrimidine 2-[4-2-(4-isopropyl phenyl)ethyl) 1000 + + phenyl]imino-hexahydropyrimidine 2-14-12-(4-ethoxyphenyl)ethyl) 1000 + phenyl]imino-hexahydropyrimidine 2-[442-(2-n-butyoxyphenyl)ethyl) 1000 + phenyl]imino-hexahydropyrimidine Example 2 In a corresponding manner as stated in Example 1, compositions were prepared of 20 mg of 2-(4-n-hexylphenyl)iminohexahydropyrimidine as an active substance dissolved in the quantities of solvent stated in Table 2; the solvent described in Example 1 was used as a solvent. The solution was replenished by the quantities of water stated in Table 2. Young tobacco plants were treated in a corresponding manner as in Example 1 and the result was evaluated after 2 weeks; the results are recorded in Table 2.

TABLE 2 Quantity of Quantity of conc. act. Evaluation of the solvent water subst. in mg/l sucker inhibiting effect 2ml 18ml 1000 ++ 5 ml 15 ml 1000 ++ 10 ml 10 ml 1000 ++ 20 ml OmI 1000 ++ When instead of 20 ml of solvent, 20 ml of pure acetone was used, the same result was obtained.

Example 3 5 g of polyoxyethylenated ricinic oil were dissolved in 3 litres of acetone. 20 mg of 2-(4-n hexyloxyphenyl)iminohexahydropyrimidine as an active substance were dissolved in 2 ml of the above-mentioned solvent, after which 10 ml of water were added.

Young tobacco plants were treated with the composition thus obtained as described in Example 1; after 2 weeks the result was judged and evaluated as +.

Example 4 Full grown tobacco plants - nearly flowering - were sprayed in the field with compositions prepared as stated in Example 1. Prior to spraying the heads of the plants were removed. Two weeks after spraying the activity of the active substances was evaluated as described in Example 1. The results recorded in Table 3 were obtained.

TABLE 3 Evaluation of the conc. in sucker inhibiting active substance mg/l effect 2-(4-n-propylphenyl)imino- 1000 + hexahydropyrimidine 750 2-(4-n-pentylphenyl)imino- 1000 ++ hexahydropyrimidine 750 + 500 + 2-(4-n-hexylphenyl)imino- 1000 ++ hexahydropyrimidine 750 ++ 500 ++ 2-(4-n-heptylphenyl)imino- 1000 ++ hexahydropyrimidine 750 ++ 500 + 2-(4-n-nonylphenyl)imino- 1000 + hexahydropyrimidine 750 + 500 + 2-(4-n-hexyloxyphenyl)imino- 1000 + hexahydropyrimidine 750 + 500 + Example 5 Full grown tomato plants were sprayed with solutions of the active substances stated in Table 4 in water-acetone mixture (9:1) in the concentrations stated.Three weeks after spraying, the activity of the active substances was determined by finding out the extent, if any, to which the development of the head and the lateral shoots had been inhibited. The results are recorded in Table 4 in which evaluation of Example 1 was used.

TABLE 4 Growth inhibiting effect on conc. in active substance mg/l head suckers 2-(4-n-hexylphenyl)imino- 3000 ++ ++ hexahydropyrimidine 1000 ++ + 300 2-(4-n-pentylphenyl)imino- 3000 + ++ hexahydropyrimidine 1000 ++ ++ 300 2-(4-n-heptylphenyl)imino- 3000 ++ ++ hexahydropyrimidine 1000 + + 300 + 2-(4-cyclohexylphenyl)imino- 3000 ++ ++ hexahydropyrimidine 1000 f + 300 2-(4-n-hexylthiophenyl)imino- 3000 + + + + hexahydropyrimidine 1000 + + 300 - 2-(4-n-hexyloxyphenyl)imino- 3000 + + + + hexahydropyrimidine 1000 + + 300 Example 6 Growth inhibition tomato.

Three week old tomato plants were sprinkled with solutions from a watering of 2-[4-(1methylheptylthio)phenyl]iminohexahydropyrimidine as an active substance in a mixture of water and acetone (9:1). After three weeks the growth was compared with non-sprinkled plants. The growth inhibition was evaluated as follows: - = no growth inhibition + = very small growth inhibition + = slight growth inhibition ++ = pronounded growth inhibition +++ = very strong growth inhibition The following results were obtained.

TABLE 5 dosage in kg/ha growth inhibition 3 +++ 1 +++ 0.5 ++ Example 7 Growth inhibition ornamental plants.

A solution of 10 g of active substance, 8 g of alkylbenzenepolyoxyethylene and 15 ml of cyclohexanone in 57 ml of xylene were emulsified in water in a quantity of 10% by volume. Plants of Poinsettia and Chrysanthemum were sprayed with this solution in the dosages stated in Table 6. The results below were obtained in which the evaluation stated in Example 6 was used.

TABLE 6 Growth inhibition dosage in active substance kg/ha Poins. Chrys.

2-(4-isopropylphenyl)imino- 2 + hexahydropyrimidine 1 - ++ 0.5 - + 2-(4-cyclohexylphenyl)imino- 2 hexahydropyrimidine 1 + 0.5 - 2-(4-n-butylphenyl)imino- 4 hexahydropyrimidine 2 Example 8 Growth inhibition of grass.

Trays with Agrostis canina and Lolium perenne were sprayed with solutions of the undermentioned active substances in acetone. After 3 days the grass was mown and the regrowth was evaluated after 2 weeks. The results recorded in Table 7 were obtained in which the evaluation stated in Example 6 was used.

TABLE 7 Growth inhibition dosage active substance in kg/ha Agrostis Lolium 2-(4-isopropylphenyl)imino- 1 ++ + hexahydropyrimidine 0.5 ++ 2-(4-cyclohexylphenyl)imino- 1 hexahydropyrimidine 0.5 ++ 2-(3,4-tetramethylenephenyl)- 3 + + + ++ imino-hexahydropyrimidine 1 0.5 2-(4-n-propylphenyl)imino- 3 +++ hexahydropyrimidine 1 +++ + 0.5 2-(4-sec.butylthiomethylphenyl) 3 ++ + imino-hexahydropyrimidine 1 - 2-(4-n-butylphenyl)imino- 3 + + + + hexahydropyrimidine 1 - dodecylbenzenesulfonate

Claims

1. A composition for use in the regulation of plant growth comprising a compound of the general formula

wherein R1 is a halogen-substituted or non-halogen-substitued alkyl-, akenyl, alkoxy, alkenyloxy-, alkylthio-, alkenylthio, alkoxyalkyl- or alkylthioalkyl group having 3 to 12 carbon atoms, a mono-, bi- or tricycloalkyl group having 3 to 12 carbon atoms, a phenyl-, phenoxy-, phenylthio, phenylalkyl-, phenylalkoxy- or phenylalkylthio group having 6 to 10 carbon atoms, which phenyl group of the phenyl group of which is substituted, if desired, with halogen or with alkyl, alkoxy, or alkylthio, which alkyl-, alkoxy- or alkylthio groups have 1 to 6 carbon atoms and, if desired, may be halogenated, or a furylalkyl- orthienylalkyl group having 5 to 8 carbon atoms, R2 is a hydrogen atom or a halogen atom, or wherein R1 and B2 together represent a trimethylene group or a tetramethylene group, R3 and R4 are equal or different and represent a hydrogen atom or an alkyl group or an alkanoyl group having 1 to 4 carbon atoms, B5 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and n isO or 1, or a salt or complex thereof and a solid or liquid inert carrier, if desired, with growth regulators, pesticidal compounds, fertilizers and/or auxiliary substances.

2. A composition as claimed in Claim 1, characterized in that the composition comprises as the active substance a compound of the general formula

wherein R'1 is an n-alkyl group having 5 to 9 carbon atoms or a phenylethyl group, or a salt or complex thereof.

3. A composition as claimed in Claim 2, characterised in that the composition comprises 2-(4-npentylphenyl)iminohexahydropyrimidine or a salt or complex thereof as the active substance.

4. A composition as claimed in Claim 2, characterised in that the composition comprises 2-(4-nhexylphenyl)iminohexahydropyrimidine or a salt or complex thereof as the active substance.

5. A composition as claimed in Claim 2, characterised in that the composition comprises 2-(4-nheptylphenyl)iminohexahydropyrimidine or a salt or complex thereof as the active substance.

6. A composition as claimed in Claim 2, characterised in that the composition comprises 2-(4-noctylphenyl)iminohexahydropyrimidine or a salt or complex thereof as the active substance.

7. A composition as claimed in Claim 2, characterised in that the composition comprises 2-(4-nnonylphenyl)iminohexahydropyrimidine or a salt or complex thereof as the active substance.

8. A composition as claimed in Claim 2, characterised in that the composition comprises 2-[4-(2 phenylethyl)phenyl]iminohexahydropyrimidine or a salt or complex thereof as the active substance.

9. A method of preparing a composition according to any one of Claims 1 to 8, characterised in that a compound of the general formula

wherein R1, R2, R3, R4, R5 and n have the meanings stated in Claim 1, or a salt or complex thereof, is mixed with a solid, or dissolved or dispersed in an liquid, inert carrier, if desired with the addition of growth-regulators, pesticidal compounds, leaf fertilizers and/or auxiliary substances, such as, wetting agents, emulsifiers, dispersing agents and stabilizers.

10. A method of regulating the growth of one or more plants or parts of plants in agriculture and horticulture, characterised in that the plant or plants is/are treated with a composition as claimed in any of the Claims 1 to 8 in a dosage corresponding to 100 to 5000 g of the active compound per hectare of land containing said plant or plants.

11. A method of inhibiting or preventing the development of suckers in agricultural and horticultural crops, characterised in that the crop is treated with a composition as claimed in any of the Claims 1 to 8 in a dosage corresponding to 100 to 5000 g of the active compound per hectare of land.

12. A compound of the general formula

wherein n isO or 1.

13. A compound of the general formula

wherein R', is a n-propyl, isopropyl, n-propylthio or tert. butyl group, and R2 is a hydrogen or a chlorine atom.

14. Acompound of the general formula

wherein m is 1 or 2, Ra is a hydrogen atom, a chlorine atom or a methyl group, and R2 is a hydrogen or a chlorine atom.

15. 1 ,3-diethyl-2-(4-n-butylphenyl)imino-hexahydropyrimidine.

16. 2-[4-(1 -methylheptylthio)phenyljimino-imidazolidine.

17. 2-(4-n-octylphenyl )imino-hexahydropyrimidine p-dodecylbenzene sulfonate.

18. 2-(4-cyclohexylphenyl)imino-hexahydropyrimidine benzothiozole thiolate.

19. 2-(4-adamantylphenyl)imino-hexahydropyrimidine.

20. 2-[4-12-(2-n-butoxyphenyl )ethyl)phenyl] iminohexahydropyrimidine.

21. A composition as claimed in Claim 1 substantially as hereinbefore described.

22. A method of preparing a composition as claimed in Claim 9 substantially as hereinbefore described.

23. A method of regulating the growth of plants or parts of plants as claimed in Claim 10 or Claim 11 substantially as hereinbefore described.

24. Novel hexahydropyrimidine and imidazoline compounds substantially as herein before described.