CA1313190C

CA1313190C - Phosphorus-containing microbicides against phytopathogenic micro-organisms

Info

Publication number: CA1313190C
Application number: CA000511101A
Authority: CA
Inventors: Ludwig Maier
Original assignee: Ciba Geigy AG
Current assignee: Novartis AG
Priority date: 1985-06-11
Filing date: 1986-06-09
Publication date: 1993-01-26
Anticipated expiration: 2010-01-26
Also published as: IE861544L; IL79086A0; EP0207890B1; KR940005339B1; PH22874A; ZA864321B; BR8602695A; DK272886D0; AU601153B2; DD251913A5; ATE50999T1; JPH0753743B2; PT82737B; AU5850986A; PT82737A; ES555882A0; GR861496B; NZ216484A; DE3669512D1; ES8800954A1

Abstract

S-15383/+
Microbicides Abstract of the Disclosure Compounds of formula I

(I), wherein R and R1 are each independently C1-C4alkoxy or hydroxy and X
and Y are as defined herein, as well as the metal, ammonium or substituted ammonium salts thereof, are useful insecticides, acaricides and, in particular, fungicides. They can be applied to plants or to the locus thereof in the form of compositions or used as seed dressings.

Description

5-15383/+

Microbicides The present invention relates to microbicides containing as at least one active ingredient an l-amino-2-ary~ethanephosphonic or l-amino-2-arylethanephosphinic acid derivative or 1-amino-2-arylethanepho-sphine oxide derlvative of formula I or a salt thereof, and to the use of these compounds for controlling harmful micro-organisms.

The compounds of the present invention have the formula R~ H-CH2-~
1 H 2 ~ y wherein R and Rl are each independently of the other Cl-C4alkyl, Cl-C4alkoxy os hydroxy, X is hydrogen, halogen, Cl-C4alkyl, Cl-C4-alkoxy, trlmethylsilyl, cyano, methoxycarbonyl or the radical -CH2-CH(NH2)-P(O)(R)(Rl), and Y is hydrogen, halogen, Cl-C2halo-alkoxy or Cl-C2haloalkyl, and salts thereof lf R andlor R1 are hydroxy.

Formula I expresses ethanephosphonic acid derivatives if R and Rl are hydroxy or alkoxy, ethanephosphinic acid derivatives if one of the two substituents R and Rl i3 alkyl, and ethanephosphine oxide derivatives if both substltuents R and Rl are alkyl.

Cl-C4Alkyl by itself or as moiety of an alkoxy group is methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl or tert-butyl.

\

Halogen denotes fluorine, chlorlne, bromlne or iodine. C1-C2Haloalk-yl by itself or as moiety of a haloalkoxy group is a monohalogenated methyl or ethyl group or a methyl or ethyl group which 19 perhalo-genated by a specific halogen atom or by differcnt halogen atoms.
Typical examples are CHC12, CHF2, CHzCl, CC13, CH2F, CHBra~
CH2CH2Cl, CHCl-CHCl, CF3, C2Fs, CF2Cl, CFz-CF2Cl.

Salts of a free hydroxyl group are unsubstituted or substituted ammonium or hydrazinium salts or metal catlons.

Examples of metal ions are the cations of the following elements:
alkali metals such as lithium, sodium or potassium; alkaline earth metals such as magnesium, calcium, strontium or barium; elements of the first to the eighth Periodic auxiliary group such as chromium, manganese, iron, cobalt, nickel, copper, zinc, silver, with iron, manganese, copper and zinc being preferred; elements of the third and fourth Periodic main group such as aluminium, silicon, tin, lead, zirconium, titanium, preferably aluminium, which metal ions may be present in the salts or complexes of formula I in the valence states appropriate to them.

Phosphonic acid derivatives of formula I can in principle be obtained by reacting an unsubstituted or substituted 2-phenylacet-aldehyde with ammonia and a dialkyl phosphite, followed by optional subsequent hydrolysis with a mineral acid:

~ ~--CHz-CHO + NH3 + H~(Oalkyl)2 y~X.=.

alkyl-O-- ~ H--CH2~-~ ~ ( H ~ HO-- ~ H2--~
lkyl ~ H \~
Chalmers and Kosolapoff, J.Am.Chem.Soc. 75, 5278 (1953)].

A mineral acid wlll be under~tood a~ m0aning preferably a hydrohallc acld 0uch as hydrochlorlc or hydrobromlc acld, sulfurlc acid, phosphoric acid, nitrlc acid, toluenesulfonic acid ant the like.

A rather more general method i9 that proposed by Berlin et al., [J.
Org. Chem. 33, 3090, (1968)], ln whlch a 0ubstitut0d phenylacetyl-halide 19 reacted with a) O,O,O-trlalkylphosphlte, b) O,O-trialkyl-phosphonite or c) O-trialkylphosphinite, and the intermediate i9 further reacted, in the presence of hydroxylamine, to give the phosphonyl, phosphinyl or oxophosphino-oxime, from which the amine can be obtained by hydrogenation:

~--CH2-COHal + ~ R* ~ ~-CH2-CO- ~ R*

NH20H ~ -CH2 ~ * R lRa-Ni~

In the above formulae, X and Y are as defined for formula I, and the remaining substituents are defined as follows:

X' ~ H, halogen, Cl-C4alkyl, Cl-C4alkoxy, Sl(CH3)3, -CN, -COOCH3 or -CH2-CHO, alkyl - Cl-C4alkyl, X* - H, halogen, Cl-C4alkyl, Cl-C4alkoxy, Si(CH3)3, -CN, -COOCH3 or -CH2-COHal, X** - H, hslogen, Cl-C4alkyl, Cl-C4alkoxy, Si(CH3)3, -CN, -COOCH3 or -CH2-C(O)-P(O) R* (R*l), Hal ~ halogen, preferably Cl or Br, R' - Cl-C4alkyl, R* - Cl-C4alkyl or Cl-C4alkoxy, R*l ' C1-C4alkyl or Cl-C4alkoxy.

. ~ . .

Formula I* embraces only those compounds of formula I, wherein R and Rl have the meaning of R* and R*l. Where R* and/or R*l are Cl-C4alk-o~y, free hydroxyl groups can be obtained therefrom by hydrolysls with, preferably, a mlneral acid. Free ~H groups can, lf desired, be converted with a base into saltg, e.g. metal salts, ammonlum salts, alkylammonium salts, dialkylammonlum salts or the like.

Compounds of formula I can be obtained ln qimple manner and in high yield by a further method by aralkylating the actlvated Schiff's base obtained from a) aminomethylphosphonate, aminomethylphosphi-nate or aminomethylphosphine oxlde, and b) an aldehyde such as benzaldehyde or a ketone such as phenylacetone or benzophenone, with a suitably substltuted benzyl halide lR.W. Radcliffe and B.G.
Christensen, Tetrahedron Letters, 4645 (1973)l:

\C=N-CH2-~R + Hal-CH2~ LiN(isoC3H7) C=N-~H-P(R)(RI) l X ~
T2 i ,_,~X ~-CH2- H- (R)(RI) Hal-CH2~-\ ~ ~ ~ / T

Hal - halogen, preferably Br or Cl The activation of the -CH2- group vicinal to the P-atom in the starting materlal can also be effected by other reagents such as butyllithium or sodium hydride in e.g. tetrahydrofuran. R, Rl, X and Y are as defined for formula I, Tl is hydrogen or an aliphatic or aromatic radical and T2 is an aliphatic or aromatic radical.

The last step of the hydrogenolytic cleavage of the Schiff's base to obtain the desired final product of formula I is carried out by catalytic cleavage with e.g. H2/PdlC, but can also be performed with hydrogen in the presence of other catalysts (such as platinum or Pt/C). In the presence of a mineral acid such as hydrochloric or hydrabromic acid, it i9 posslble to carry out the eleavage of ths 5chiff's base and the hydrolysis of an alkoxy group to a hydroxyl group - provided at least one of the substituents R and/or Rl is alkoxy - at elevated temperature (40-150C) in one reaetlon step.
It is advantageous to use inert solvents or diluents in all the aforemen-tloned procedures. Examples of eustomary solvents and diluents are aliphatie and aromatlc hydrocarbons such 85 benzene, toluene, xylenes, petroleum ether; halogenated hydrocarbons such a~
chlorobenzenes, methylene chloride, ethylene chloride, chloroform, tetrachloroethylene; ethers and ethereal compounds such as dialkyl ethers (diethyl ether, dlisopropyl ether, tert-butylmethyl ether and the like), anisole, dioxsne, tetrahydrofuran; nltrlles such as acetonitrile, propionitrile, and mixtures of such golvents wlth one another.

The reaction temperature during the aralkylation (benzylation) is normally in the range from -100 to +10C, preferably from -80 to -20C. The hydrogenolytic cleavage ls conveniently carried out in the temperature range from -20 to +80C.

The clted startlng compounds are known or are prepared by methods known per se. To prepare the Schlff'Y base, lt is advantageous to carry out the process ln an inert gaY such as nltrogen or argon.
Substltuted benzyl bromides can be readlly obtained from suitably substltutet toluenes by bromination wlth N-bromosuccinlmlde ln CCl4 in the presence of azoisobutyronltrile ~catalyst).

The compounds of formula I are phosphonyl, phosphinyl ant oxophos-phino analogs of ~-phenylalanine. As such they poYsess, adjacent to the P-atom, an asymmetrical carbon atom, such that the structures corresponding to the natural L-a-amino acids have the (R)-configur-ation, whereas the structures of formula I corresponding to the D-a-amino acids have the (S)-configurstion. The respective (R~- or (S)-eonfigurations of a diastereoisomeric (R,S)-compound can be - 6 - ~313190 obtained pure therefrom by fractional crystallisation or chromato-graphy (HPl.C). The (R)-diastereoisomers and (S)-diastereoisomers have different microbicidal properties.

The presene invention also relate3 to the above pseparatory methods, where these lead to novel compounds. The inventlon further relates to the novel compounds of formula I in which at least one of the substituents X and Y has a meaning different from hydrogen, provided R and R1 are simultaneously hydroxy or ethoxy.

Compounds of formula I, wherein R and Rl are Cl-CI,alkoxy, are valuable acaricides (in particular against Tetranychus and Amblyomma species) as well as lnsecticides which are effective in particular against sucking insects (aphicides).

Preferred microbicides are compounds of formula I and salts thereof, wherein R is Cl-C4alkyl or OH, Rl is OH, X is hydrogen, halogen, Cl-C4alkyl, C1-C4alkoxy, Si(CH3), -CN, -COOCH3 or CH2-CH(NH2)-P(O)(R)(RI), and Y i9 hydrogen, halogen, halomethoxy, haloethoxy or halomethyl.

Among these microbicides, those compounds are preferred wherein R ~ Rl - OH, X ls hydrogen, fluorine, chlorine or bromine, Cl-C4alkyl, CH30, Si(CH3)3, -CN, -COOCH3 or -CHz-CH(NH2)-P(O)(OH) 2. and Y is fluorine, chlorine, bromine, halomethoxy or halomethyl.

Among these last mentioned microbicides, those compounds are particularly preferred in which at least one of the substituents X
and Y is or contains halogen, and, of these, thoss compounds in which one of the substituents X and Y i8 or contains fluorine.

.

Another important subgroup of microbicidally actlve compounds are those compounds of formula I and salts thereof wherein R and R1 are each independently of the other C1-C4alkyl, C1-C4alkoxy or hydroxy, X is halogen, C1-C4alkyl, C1-C4alkoxy, Sl(CH3)3, cyano or -CH2-CH(NH2)-P(O)(R)(R1), Y i8 hydrogen, halogen, halomethoxy, haloethoxy or halomethyl.

Among these last mentioned microbicides, those compounds are especially important wherein R, R1 and Y have the given meanings and X is fluorine, chlorine, methyl, ethyl, isopropyl, tert-butyl, methoxy, ethoxy, isopropoxy or cyano.

Also lmportant are microbicidal compounds and salts thereof in which R and R1 are as defined for formula I, X is halogen, methyl, methoxy or cyano, and Y is hydrogen, halogen, OCHFz or CF3.

Another important group of microbicides comprises those compounds of formula I, wherein R and R1 are as previously defined, X is hydrogen and Y is difluoromethoxy or trifluoromethyl.

Derivatives of peptidylaminomethanephosphonic and peptidylamino-phosphinic acid are disclosed in US patent specification 4 016 148 as potentiators for antibiotics. However, no particulars relating to pest control are contained therein and such utility is in no way suggested.

Peptidylaminoalkanephosphonic acid derivatives are proposed as herbicides and retarders for plant growth and plant emergence in US
patent specification 4 431 438. However, there is no mention of protecting plants agsinst microbial attack. It must also be added that compositions with general herbicidal or growth inhibiting properties are of necessity very poorly suited to protecting cultlvated plants.

Surprisingly, it has now been found that the aminoethanephosphonlc acid derivatiYe3 of formula I and salts thereof not only have no herbicidal properties, but have an unexpectedly potent microblcidal activity which is particularly suitable for imparting lastlng protection to plants from attack by fungi and bacteria and for promoting the development of said plants.

Provided at least one of the substituents R and Rl i9 an OH group, the salts of formula I come into the category of preferred com-pounds. Especially preferred on account of their fungicidal activity are the metal salts, in particular the aluminium, nickel, manganese and copper salts and the lower alkylammonlum salts of formula I, which are particularly suitable for soil application and as seed dressing agent.

The principal utility of compounds of formula I is for controlling harmful phytopathogenic fungi. Thus the compounds of formula I have, for practical purposes, a very useful curative, preventive and systemic action for protecting cultivated plants without adversely affecting said plants by undesirable side-effects. Examples of cultivated plants within the scope of this invention are: cereals (whest, barley, rye, oats, rice); beet (sugsr beet and fodder beet), drupes, pomes and soft fruit (apples, pears, plums, peaches, almonds, cherries, strawberries, raspberries and blackberries), leguminous plants (beanst lentils, peas, soybeans); oil plants (rape, mustard, poppy, olives, sunflowers, coconuts, castor oil plants, cocoa beans, groundnuts); cucumber plants (cucumber, marrows, melons); fibre plants (cotton, flax, hemp, ~ute~; citrus fruit (oranges, lemons, grapefruit, mandarins); vegetables (spinach, lettuce, asparagus, cabbages, carrots, onions, tomatoes, potatoe~, paprika); or plants such as maize, tobacco, nuts, coffee, sugar cane, tea, vines, hops, bananas, avocados, and natural rubber plants, as well as ornamentals.

With the compounds of formula I lt 1~ posslble to inhlblt or destroy the micro-organisms whlch occur in plants or parts of plants (frult, blossoms, leaves, stems, tubers, roots~ in these and in related crops of useful plants, while at the sAme time the pArts of plants which grow later are also protected from attack by such micro-orga-nisms.

The compounds of formula I are particularly effective agalnst the phytopathogenic fungi belonging to the following classes: Ascomy-cetes (e.g~ Helminthosporium and Fusarium species) and Basidomycetes (e.g. Tilletia and Ustilago). The compounds of formula I can therefore also be used as seed dressing agents for protecting seeds (fruit, tubers, grains) and plant cuttings against fungus infections 8S well as against phytopathogenic fungi which occur in the soil.

Accordingly, the invention also relates to the use of compounds of formula I for controlling phytopathogenic micro-organisms and for the preventive treatment of plants to protect them from attack by such micro-organisms.

The compounds of formula I are normally applied in the form of compositions and can be applied to the crop area or plant to be treated, simultaneously or in succession, with further compounds.
These compounds can be both fertilisers or micronutrient donors or other preparations that influence plant growth. They can also be selective herbicides, fungicides, bactericides, nematicides, molluscicides or mixtures of several of these preparations, if deslred together with further carriers, surfactants or application promoting ad~uvants customarily employed in the art of formulation.
Suitable carrlers and ad~uvants can be solid or llquid and corres-pond to the substances ordinarlly employed ln formulatlon tech-nology, e.g. natural or regenerated mlneral substances, solvents, dlspersants, wetting agents, tackifiers, thickeners, binders or fertilisers.

- ~o 1313190 The compounds of ~lle Pormula I are used ln unmodiEled form or, preferably, together with the ad~uvantg conventlonally employed in the art of formulation, and are therefore formulated in known manner to emulsifiable concentrates, coatable pastes, directly sprayable or dilutable solutions, dilute emulsions, wettable powders, soluble powders, dusts, granulates, and also encapsulations in e.g. poly-meric substances. As with the nature of the compositions, the methods of application, such as spraying, atomising, dusting, scattering or pouring, are chosen in accordance with the lntended objectives and the prevailing circumstances. Advantageous rates of application in agriculture are normally from 50 g to 5 kg of active ingredient (a.i.~ per hectare, preferably from 100 g to 2 kg a.i./ha, most preferably from 100 g to 600 g a.i./ha.

Suitable solvents are: aromatic hydrocarbons, preferably the fractions containing 8 to 12 carbon atoms, e.g. xylene mixtures or substituted naphthalenes, phthalates such as dibutyl phthalate or dioctyl phthalate, aliphatic hydrocarbons such as cyclohexane or paraffins, alcohols and glycols and their ethers and esters, such as ethanol, ethylene glycol monomethyl or monoethyl ether, ketones such as cyclohexanone, strongly polar solvents such 8S N-methyl-2-pyrro-lidone, dimethylsulfoxide or dimethylformamide, as well as epoxid-ised vegetable oils such as epoxidised coconut oil or soybean oil;
or water.

Particularly useful application-promoting ad~uvants which are able to reduce substantially the rate of application are also natural (animal or vegetable) or synthetic phospholipids of the series of the cephalins and lecithins, e.g. phosphatidyl ethanolamine, phosphatidyl serine, phosphatidyl glycerol or lysolecithin.

Depending on the nature of the compound of the formula I to be formulated, suitable surface-active compounds are nonionic, cationic and/or anionic sufactants having good emulsifying, dispersing and wetting properties. The term "surfactants" will also be understood as comprising mixtures of surfactants.

,1 1313190 The surfactants customarily employed in the art of forMulation are described e.g. in "McCutcheon'g Detergents and Emulsiflers Annual", MC Publishing Corp. Ridgewood, New Jersey, 1981; Helmut Stache "Tensid-Taschenbuch" (Surfactant Handbook) Carl Han~er Verlag, Munich~Vienna, 1981; M. and J. Ash, Encyclopedia of Surfactants, Vol I-III, Chemical Publighing Co., New York, 1980-1981.

The agrochemical compositions usually contain 0.1 to 99 %, prefer-ably 0.1 to 95 %, of a compound of formula I, 99.9 to 1 %, prefer-ably 99.8 to 5 %, of a solid or liquid adjuvant, and 0 to 25 %, preferably 0.1 to 25 %, of a surfactant.

Whereas commercial products are preferably formulated as concen-trates, the end user will normally employ dilute formulations.

The invention is illustrated in more detail by the following Examples, without implying any restriction to what is de~cribed therein. Parts and percentages are by weight.

Preparatory Examples Example 1: Preparation of 0,0-diisopropyl-1-amino-2-(4-fluoro-phenyl)ethYlphosphonate of formula isoC3H70- ~ ~H-CH2~ -F ~compound 1.8]
C3H7iso ~=~

a) Preparation of O,0-diisopropyl-1-N-benzylidenamino-2-(4-fluoro-phenyl)ethYlphosphonate (intermediate) With stirring and cooling, 500 ml of n-butyllithium are added to 113.4 g (0.8 mole) of diisopropylamine in 750 ml of tetrahydrofuran (THF). The mixture i9 cooled to -75C and then a solution of 226.6 g (0.8 mole) of 0,0-diisopropylbenzylideneaminomethanephosphonate in 600 ml of THF i9 added dropwise over the course of 1 hour. After stirring for 1 hour, a solutlon of 151.2 g (0.8 mole) of 4-fluoro-benzyl bromide in 150 ml of T~F is added dropwise and stirring i5 continued for 1 hour. After the reaction mixture has stood overnight at room temperature, the solvent is strlpped off and the residue i9 dissolved in 1 litre of dichloromethane. The solution i9 washed wlth three 200 ml portions of water and dried over Na2S04. The solvent ls then removed by evaporation to give 286.3 g (91.4 % of theory) of the intermediate, which yields 261.2 g (83.4 % of theory) of pure product after molecular distillation. Boiling point: 160C/0.1 mbar.

b) Preparation of the final Product To a solution of 19.6 g (0.05 mole) of the intermediate obtained in la) in 200 ml of isopropanol are added 2 g of PdlC (5 % Pd) and the mixture is hydrogenated at room temperature (20-25C). After 62 %
hydrogen uptake, 2 g of PdlC are again added and, after 90 %
hydrogen uptake, a further 2 g of Pd/C are added. The hydrogen uptake is complete after 19 hours. The reaction mixture is filtered and the filtrate is concentrated by rotary evaporation. The residue (ca. 15 g) is distilled in a bomb tube, affording 12.6 g (83.1 % of theory) of pure final product in the form of a colourless oil with a boiling point of 170C/0.08 mbar.

Example 2: Preparation of 1-amino-2-(4-fluorophenyl)ethanephosphonic acid (compound 2.6) A mixture of 227.5 g (0.75 mole) of 0,0-diisopropyl-1-amino-2-(4-fluorophenyl)ethylphosphonate and 750 ml of 20 % hydrochloric acid is refluxed, with stirring, for 5 hours and stirred for a further 5 hours at room temperature. After addition of 500 ml of water, the precipitate is filtered and washed with 250 ml of water and 500 ml of methanol. Yield: 103.3 g of title compound. The filtrate is concentrated and the residue is recrystallised from methanollpropylene oxide, affording a further 43.3 g of final product. Total yield: 146.6 g (89.2 % of theory). Melting point:
266-270C (dec.).

-Example 3: Preparation of the optical igomer9 of 1-amino-2-(4-fluoro-phenyl)ethanephosphonic acid A. Preparation of the dibenzoyl tartrates of O,O-diathYl-l-amlno-?-~4-fluorophenyl)ethylphos~honate (EtO)2P-CH-CH2~ F + (C6H~COOCH-COOH)2 ~ salt a) To a solution of 68.82 g (0.125 mole) of O,O-diethyl-l-amlno-2-~4-fluorophenyl)ethylphosphonate in 750 ml of methanol and 750 ml of ethanol are added 47.04 g of dibenzoyltartaric acid (L)(-)xH20.
After stirring for 2 hours, the thick white suspension is filtered and the residue is dried. Two recrystallisations from ethanol yield 31.5 g (39.8 % of theory) of "salt I" of m.p. 179C (dec.);
[ ]D = -66.4 + 0.5 (c ~ 2.077 % in methanol).

b) The combined residual filtrates are evaporated and the residue is stirred in lN NaOH. The solution is saturated with sodium chloride and extracted with three 400 ml portions of CH2Cl2. The organic phase is dried over Na2SO4 and concentrated by evaporation. The residual brown oil (37.5 g) is dissolved in 400 ml of methanol and 400 ml of ethanol and 25.6 g of dibenzoyltartaric acid (D)(+)xHzO, are added to the solution. After stirring for 2 hours, 63 g of salt are lsolated by filtration and recrystallised from 1200 ml of methanol to give 7.2 g of crude "salt II". The filtrate is concen-trated and the residue recrystallised from 500 ml of ethanol, affording 17 g of pure "salt II"; [~D0~ +673 + 0.5 (c - 1.998 %
in methanol).

a) Preparation of (+) O,O-diethyl-l-amino-2-(4-fluorophenyl)ethyl-phosphonate 25.34 g of salt I are stirred for 2 hours at room temperature in 100 ml of lN NaOH to effect liberation from the tartrate. The clear solution is saturated with sodium chloride, then 200 ml of CH2C12 - 14 - 131~190 are added and ~he resultant suspenslon i9 flltered in vacuo. The residue i6 washed with two 200 ml portions of CH2Cl2. The organlc phase of the combined filtrates i9 separated, dried over NazSO4, filtered, and concentrated by evaporation to give 9.1 g (a2.7 % of theory) of the deRired final product as a pale yellow oil:
[~]D 3 +10.6 + 0.4 (c ~ 2.5 % in methanol).
1H-NMR in CDCl~: 1.3 (NH2, CH3~(t, 8H); 2.3-3.5 (PCH-CH2) (m, 3H);
4.17 (OCH2)(qu, 4H); 7.1 (m) (4H, phenyl).

b) Preparation of (+) l-amino-2-(4-fluoro~ yl)ethanePhosphonic acid 5.51 g (0.02 mole) of the (+) phosphonate obtained in a) are refluxed in 40 ml of 20 % hydrochloric acid for 4 hours. The solution is then concentrated and the residue is recrystallised from methanol/propylene oxide, affording 3.7 g (84.5 % of theory) of the desired final product. Melting point: 259-263C (dec.);
[~]DO~ +37.5 + 0.4 (c ~ 2.636 % in 1 N NaOH).
H NMR in D2OtNaOD: 2.3-3.1 (PCH-CH2)(m, 3H); 4.65 (OH, NH2) (s);
6.6-7.1 (phenyl, 4H)(m).

a) PreParation of (-) O,O-diethyl-l-amino-2-(4-fluorophenyl)ethyl-phosphonate in accordance with the method of Ba) from "salt II" with lN NaOH solutlon.
Yield: 95.9 % of theory. Pale yellow oil 1~]D~ -10.3 + 0.5 (c ~ 2.036 in methanol).

b) Preparation of (-) l-amino-2-(4-fluoroPhenyl)ethanephosphonic acid in accordance with the method of Bb) by hydrolysis of the above (-) pho~phonate in 20 % hydrochloric acid. Yield: 77.6 % of theory.
Nelting point: 261-263C (dec.).
E~]DO~ -36.9 + 0.5 (c n 2.081 % in lN NaOH).
H-NMR in D2OINaOD: 2.5-3.4 (PCH-CH2)(m, 3H); 4.85 (OH, NH2) (s);
6.8-7.4 (phenyl, 4H) (m).

The Pollowlng compaunds of Pormula I, whlch are obtained fl8 mlxtur~s of diastereoisomers unless otherwlse Apecifically mentioned, can also be prepared in this manner or by one of the other methods described above.

The ~H-NMR values were determined with a Varlan EM~-360 ~pectrometer -bt 60 MHz in CDC13 with (CH3)4Si as reference substance.

The 3~P-NMR values were recorded with 8 Bruker WP 80 spectrometer at 32.28 MHz wlth 85 % H3P04 (externally) as reference substance.

Key:
Me - methyl Et ~ ethyl iPr = isopropyl The temperatures are given in degrees centigrade.

~ rrc~de-~k Table 1:

Compounds of formula (R'O)z ~CH(NH2)-CH2~

Compound R' X Y Phy~ical data 1.1 Et H H b.p. 17010.6 mbar 1.2 iPr H H lH:1.3(NHz), 2.5-3.5(PCH-CH2) 7.3 (aromatic-H) 1.3 Et 4-Cl H nD1.5140 1.4 Et 3-Cl H IH:1.3; 2.4-3.5; 7.2 1.5 Et 4-Br H b.p. 125/0.05 mbar 1.6 Et 4-I H IH: 1.3; 2.3-3.4; 7.767 1.7 Et 4-P H b.p. 150-160/0.08 mbar 1.8 iPr 4-F H b.p. 17010.08 mbar 1.9 iPr 3-F H b.p. 150/0.05 mbar 1.10 iPr 2-F H b.p. 15010.08 mbar 1.11 Et 2-C1 4-Cl m.p. 59-62 1.12 Et 3-Cl 4-Cl nD 1.5272 1.13 Et 4-Me H 1H: 1.4; 2.5-3.5; 7.15;
2.32 (X~CH3). 31p 28.09 1.14 Et 3-Me H nD 1.5060 1.15 Et 2-Me H 1H: 1.33; 2.5-3.5; 7.2;
2.33 (X~CH3). 31p 28.19 1.16 Et 3-CF3 H nD1.4659 1.17 iPr 4-t-butyl H b.p. 140l0.01 mbar 1.18 Et 4-MeO H b.p. 165/0.2 mbar 1.19 Et 2-MeO H b.p. 125/O.l mbar 1.20 Et 2-P 6-Cl 1.21 Et H 4-OCHFz 1.22 Et H 3-OCHFz 1.23 iPr H 4-OCHF2 1.24 iPr H 4-CF3 1.25 iPr H 4-CHFz _ 17 _ 1313190 Table 1: ~continuation~

Compound~3 of formula (R~0)2~CH(NH2)-CH2~

Compound R' X Y Physical data 1.26 Et H 4-oC2Fs 1.27 Et H 4-OCF2-CFzCl 1.28 Et 2-Si(Me)3 H b.p. 110/0.1 mbar 1.29 Et 3-Sl(Me)3 H b.p. 150/0.12 mbar 1.30 Et 4-Sl(Me)3 H b.p. 120/0.1 mbar 1.31 iPr 4-CN H 1H: 1.35; 2.6-3.5; 7.4-7.6 1.32 Et 3-F 4-F b.p. 115/0.1 mbar 1.33 Et 2-F 4-F b.p. 110/0.08 mbar 1.34 lPr 2-C1 3-Cl b.p. 160/0.1 mbar 1.35 lPr 3-I H
1.36 iPr 4-COOCH3 H b.p. 160/0.08 mbar 1.37 Et 4-CH2-CH-(NH2)-P(O)-(OEt)z H
1.38 Et 2-C1 4-F
1.39 Et 2-F 6-F b.p. 105/0.1 mbar 1.40 Et 2-F H b.p. 95/0.1 mbar Table 2:

Compounds of formula (HO)2 ~CH(NHz)CH2~

Compound X Y Meltin~ po~nt (m.p.) 1 dec . ]
. .
2.1 H H 278-282 2.2 4-Cl H 280-282 2.3 3-Cl H 268-272 2.4 4-Br H 284-286 2.5 4-I H 255-259 2.6 4-F H 266-270 2.7 3-F H 278-280 2.8 2-F H 275-276 2.9 2-C1 4-C1 279-280 2.10 3-C1 4-C1 274-278 2.11 4-Me H 276-279 2.12 3-Me H 270-273 2.13 2-Me H 244-245 2.14 H 3-CF3 258-262 2.15 4-t-butyl H 264-268 2.16 4-OMe H
2.17 2-OMe H
2.18 2-F 6-Cl 2.19 H 4-OCHFz 232-236 2.20 H 3-OCHF2 2.21 H 4-CF3 2.22 H 4-CHF2 2.23 H 4-oC2Fs 2.24 H 4-OCF2-CF2Cl 2.25 2-Si(Me)3 H
2.26 3-Si(Me)3 H
2.27 4-Si(Me)3 H

Tabl~ 2: (continuation) Compound X Y Melting point (m.p.) [dec.]

2.28 4-CN H 267-269 2.29 3-F 4-F
2.30 2-F 4-F 271-274 2.31 2-Cl 3-Cl 2.32 3-I H
2.33 4-CH 2 -CH(NH 2 ) -p(o) ( OH) 2 H
2.34 2-Cl 4-F
2.35 3-Me 4-Cl 2.36 2-Me 4-F
2.37 2-F 6-F 258-261 - 20 - ~ 3 1 3 1 9 0 Table 3:

Compound~ of formula R~ H-CH2-~
H H2 '= ~

Compound R X Y m.p. Idec- ]

3.1 Me H H 261-262 3.2 Et 2-Me H 234-235 3.3 Et 3-Me H 229-232 3.4 Et 4-Me H 233-236 3.5 Me 4-F H 254-257 3.6 Me 4-Br H 254-257 3.7 Me 4-Cl H 242-245 3.8 Me 3-Me H 260-262 3.9 Et H H 230-231 3.10 Me 3-Cl H
3.11 Me 3-F H
3.12 Me 2-F H
3.13 Et 2-F 6-Cl 3.14 Me 2-C1 4-Cl 3.15 Me 3-C1 4-Cl 3.16 Et 2-C1 3-Cl 3.17 Me H 3-CF3 3.18 Me H 4-OCHF2 3.19 Me 4-OCzHs H
3.20 Me 4-t-butyl H
3.21 Me H 4-OCzFs 3.22 Et 2-C1 4-F

Table 4:

Compound~ of formula (CH3)2~-~H-CH2-~ ~

Compou~d X Y Physical data 4.1 H H b.p. 160-17010.05 mbar 4.2 4-F H
4.3 4-Cl H
4.4 2-C1 4-Cl 4.5 2-C1 4-F
4.6 H 4-OCHFz 4.7 H 3-CF3 4.8 4-t-butyl H
4.9 4-CN H
4.10 4-Si(Me) 3 H
4.11 4-OMe H
4.12 4-OMe 2-Cl 4.13 H 3-OCHF 2 4.14 2-Me H b.p. 160/0.05 mbar 4.15 2-Me 4-Cl 4.16 3-Me 2-Cl 4.17 3-Me H b.p. 160/0.07 mbar 4.18 4-Me H b.p. 150-55l0.1 mbar 4.19 H 4-OC2F5 4.20 2-F 6-Cl 4.21 3-F H

Table 5:

Compounds of formula (M~O)zP-CH(NH2)CHz~

Compound M~ X Y Physical data 5.1 Na+ H H m.p. ~280 (dec.) 5.2 1/2 Mg H H
5.3 1/3 Al H H
5.4 1/2 Mn 4-F H
5.5 1/2 Ni 4-F H
5.6 1/3 Al~++ 4-F H
5.7 112 Zn 4-F H
5.8 1/4 Zr4 4-Cl H
5.9 1/2 Mn 4-Cl H
5.10 1/2 Co 4-Cl H
5.11 1/3 Al 2-C1 4-F
5.12 1/2 Cu 2-C1 4-F
5.13 1/2 Cu 4-F H m.p. >300~ (dec.) 5.14 1/3 Fe 4-F H
5.15 1/2 Ca H 4-OCHF2 5.16 1/3 Al H 4-OCHF2 5.17 1/2 Cu 4-CN H
5.18 1/3 Al 2-C1 6-F
5.19 1/2 Mn 2-C1 6-F
5.20 1/2 Ca 2-Me 4-F
5.21 (MeNH3) 4-F H m.p. 275-285(dec.) 5.22 (isoC3H7NH3) H CF3 5.23 (C6HsNH3) 2-C1 4-F

.r \

Formulation Ex~mPle~ for active in~redlent~ (compound~) of formula I (throughout, percenta~es are by weight) Fl. Solutions a) b) c) d) a compound of Tables 1 to 5 80 % 10 % 5 X 95 %
ethylene glycol monomethyl ether 20 % - - -polyethylene glycol 400 ~ 70 %
N-methyl-2-pyrrolidone - 20 %
epoxidised coconut oil - -1 % 5 Yo peeroleum distillate (boiling rsnge 160-190) 94 %

These solutions are suitable for applicatlon in the form of micro-drops.

F2. Granulates a)b) a compound of Tables 1 to 5 5 % 10 %
kaolin 94 %
highly dispersed silicic acid 1 %
attapulgite -90 %

The active ingredient is dissolved in methylene chloride, the solution is sprayed onto the carrier, and the solvent is subsequent-ly evaporated off in vacuo.

F3. Dusts a) b) a compound of Tables 1 to 5 2 % 5 %
highly dispersed silicic acid 1 % 5 %
talcum 97 %
kaolin - 90 %

Ready-for-use dusts are obtained by intimately mixing the carriers ~ with the active ingredient.

: ~' 13131~0 ~ 24 -F4. Wettable powders a) b) c?
a compound of Tables 1 to 5 25 % 50 % 75 %
sodium lignosulfonate 5 % S %
sodium lauryl sulfate 3 % - 5 %
sodium dlisobutylnaphthalenesulfonate - 6 % 10 %
octylphenol polyethylene glycol ether t7-8 moles of ethylene oxide) - 2 %
highly dlspersed silicic acid 5 % 10 % 10 %
kaolin 62 % 27 %

The active ingredient is thoroughly mixed with the ad~uvants and the mixtures is thoroughly ground in a suitable mill, affording wettable powders which can be diluted with water to give suspensions of the desired concentration and which are particularly suitable for seed dressing.

F5. Emulsifiable concentrate a compound of Tables 1 to 5 10 %
octylphenol polyethlene glycol ether (4-5 moles of ethylene oxide) 3 %
calcium dodecylbenzenesulfonate 3 %
castor oil polyglycol ether (36 mole~ of ethylene oxide~ 4 %
cyclohexanone 30 %
xylene mixture 50 %

Emulsions of any required concentration can be obtained from this concentrate by dilution with water. These emulsions are particularly sultable for seed dressing.

Blological Examples:
xample B1: Action against Botrvtis cinerea on beans ~esidual protective action Bean plants about 10 cm in height are sprayed with a spray mixture (0.02 %) prepared from a wettable powder formulation of the test compound. After 48 hours the treated plants are infected with a conidia suspension of the fungus. The infect~d plants are lncubated for 3 days at 95-100 % relative humidity and 21C and then an evaluation of fungus attack is made. Botrytis attack is 100 % on untreated, infected bean plants. Attac~ i8 less than 20 % after treatment with one of the compounds of formula I. No attack (0-5 %~
is observed after treatment wlth e.g. compounds 1.5, 2.6, 2.11, 3.4, 2.15, 2.37, 5.13 and others.

Example B2: Action against Fusarium nivale in rye (seed dressing) Rye seeds of the Tetrahel ariety which are naturally infected with Fusarium nivale are dressed on a mixer roll with the test funglcide at concentrations of 600 and 200 ppm of actlve ingredient (based on the weight of the seeds). The infected and treated rye is sown in October in the open with a seeder in plots 3 metres long and in 6 rows. Three replicates are carried out with each test compound at its given concentration. Until evaluation is made, the test plants are cultivated under normal field conditions, preferably ln a region with unbroken snow covsr durlng the winter months. To evaluate the phytotoxicity, an assessment is made of emergence in the autumn and population density and tillering in the spring. To determine-the effectiveness of the test compounds, the percentage of plants attacked by Fusarium is assessed in the spring directly after the snow has melted.

The tested compounds of formula I exhibited scarcely any or no phytoxicity. Compounds 1.5, 1.8, 2.1, 2.2, 2.6, 2.8, 2.34 and others inhibited Fusarium attack completely at both given concentrationa.

Example B3: Action against Helminthosporium ~ramineum on barle-~(seed dressing) Seeds of winter barley of the "Cl" variety which are naturally infected with Helminthosporium gramineum are dressed on a mixer roll with the test fungicide at concentrations of 600 and 200 ppm of active ingredient (based on the weight of the seeds). The infected and treated barley i9 sown in October in the open with a seeder in plots 2 metres long and in 3 rows. Three replicates are carried out ~ Ir~e ~Q,k with each test compound at its given concentration. Untll evaluation i8 made, the test plants are cultivated under normal field condit-ions. To evaluate the phytotoxicity, an assessment is made of emergence in the autumn and population density and tillering in the spring. To determine the effectiveness of the test compounds, the percentage of stalks attacked by Helminthosporium i9 assessed at the time of ear emergence.

The test compounds of formula I exhibited scarcely any or no phytotoxicity. At both given concentrations, compounds 1.28, 2.2, 2.6, 2.9, 2.30, 3.5 and others inhibited fungus attack to less than 20 % compared with untreated control plants.

Example B4: Action against Ustilago nuda on barley (seed dressing) Seeds of winter barley of the "RMl" variety which are naturally infected with Ustilago nuda are dressed on a mixer roll with the test fungicide at concentrations of 600 and 200 ppm of active ingredient (based on the weight of the seeds). The infected and treat0d barley is sown in October in the open with a seeder in plots 2 metres long and in 3 rows. Three replicates are carried out with each test compound at its given concentration. Until evaluation is made, the test plants are cultivated under normal field conditions.
To determine the effectiveness of the test compounds, the percentage of ears attacked by Ustilago is assessed during flowering.

Compounds 2.6, 2.10, 2.15, 2.19, 5.21 and others reduced fungus attack at both given concentrations to less than 20 %.

Example B5: Action a~ainst Tilletia tritici (seed dressing~
Seeds of winter wheat of the Probus variety which are artificially infected with smut spores of Tilletia triticl (3 g of dry spore material per l kg of seeds) are dressed on a mixer roll with the test fungicide at concentrations of 600 and 200 ppm of active ingredient (based on the weight of the seeds). The infected and treated wheat is sown in October in the open with a seeder in plots 2 metres long and in 3 rows. Three replicates are carried out with .~

each test compount at its glven concentratlon. Untll ear rlpening, the test plants are cultivated under normal field condltions. To evaluate the phytotoxlcity, an assessment i8 made of emergence ln the autumn and population density and tlllering ln the spring. To determine the effectiveness of the te~t compounds, the percentage of ears attacked by Tilletia trltlcl i9 aB9eBBed at the time of ear ripening.

At both given concentratlons, compounds of formula I, e.g. 1.5, 2.8, 1.28, exhlbited a marked protective action agalnst attack by Tllletia tritici, whereby emergence and growth of the wheat plants were favourably promoted.

Claims

1. A process for controlling phytopathogenic micro-organisms in cultivated plants or for protecting said plants from attack by such micro-organisms, which comprises applying to said plants, to parts thereof or to the locus thereof an effective amount of a compound of formula I, or of a composition including a compound of formula I as an active ingredient, (I), wherein R and R1 are each independently of the other C1-C4alkyl, C1-C4alkoxy or hydroxy, X is hydrogen, halogen, C1-C4alkyl, C1-C4-alkoxy, trimethylsilyl, cyano, methoxycarbonyl or the radical -CH2-CH(NH2)-P(O)(R)(R1), and Y is hydrogen, halogen, C1-C2haloalk-oxy or C1-C2haloalkyl, or a salt thereof if R or R1 are hydroxy.

2. A process according to claim 1 wherein, in the compound of formula I, R is C1-C4alkyl or OH, R1 is OH, X is hydrogen, halogen, C1-C4alkyl, C1-C4alkoxy, Si(CH3)3, -CN, -COOCH3 or CH2-CH(NH2)-P(O)(R)(R1), and Y is hydrogen, halogen, halomethoxy, haloethoxy or halomethyl.

3. A process according to claim 2, wherein, in the compound of formula I, R = R1 = OH, X is hydrogen, fluorine, chlorine or bromine, C1-C4alkyl, CH3O, Si(CH3)3, -CN, -COOCH3 or -CH2-CH(NH2)-P(O)(OH)2, and Y is fluorine, chlorine, bromine, halomethoxy or halomethyl.

4. A process according to claim 3, wherein, in the compound of formula I, Y is, or contains, fluorine.

5. A process according to claim 1 wherein, in the compound of formula I, R and R1 are each independently of the other C1-C4alkyl, C1-C4alkoxy or hydroxy, X is halogen, C1-C4alkyl, C1-C4alkoxy, Si(CH3)3, cyano or -CH2-CH(NH2)-P(O)(R)(R1), and Y is hydrogen, halogen, halomethoxy, haloethoxy or halomethyl.

6. A process according to claim 5, wherein, in the compound of formula I, X is fluorine, chlorine, methyl, ethyl, isopropyl, tert-butyl, methoxy, ethoxy, isopropoxy or cyano.

7. A process according to claim 1, wherein, in the compound of formula I, X is halogen, methyl, methoxy or cyano, and Y is hydrogen, halogen, difluoromethoxy or trifluoromethyl.

8. A process according to claim 1, wherein, in the compound of formula I, X is hydrogen and Y is difluoromethoxy or trifluoromethyl.

9. A process according to claim 1 wherein the compound of formula I is 1-amino-2-(4-methoxyphenyl)ethanephosphonic acid.

10. A process according to claim 1, wherein the compound of formula I is 1-amino-2-phenylethanephosphonic acid.

11. A process according to claim 1, wherein the compound of formula I is 1-amino-2-(4-fluorophenyl)ethanephosphonic acid.

12. A process according to claim 1, wherein the parts of plants to be treated are seeds.

13. A process for the preparation of a compound of formula I
(I), wherein R and R1 are each independently of the other C1-C4alkyl, C1-C4alkoxy or hydroxy, X is hydrogen, halogen, C1-C4alkyl, C1-C4alkoxy, trimethylsilyl, cyano, methoxycarbonyl or the radical -CH2-CH(NH2)-P(O)(R)(R1), and Y is hydrogen, halogen, C1-C2haloalkoxy or C1-C2haloalkyl, with the proviso that at least one of the substituents X and Y has a meaning different from hydrogen if R and R1 are simultaneously 30a 21489-6957 hydroxy or ethoxy, which process comprises activating the CH2 group of a Schiff's base of formula and then aralkylating the activated bass with a suitably substi-tuted benzyl halide of formula Hal-CH2- and cleaving the intermediate of formula hydrogenolytically in the presence of a catalyst, optionally followed by further treatment with a mineral acid at elevated temperature, provided R or R1 are alkoxy and shall be con-verted into a hydroxyl group, the substituents R, R1, X and Y in the intermediates of the above formulae being as defined for for-mula I, and T1 is hydrogen or an aliphatic or aromatic radical and T2 is an aliphatic or aromatic radical, and Hal is a halogen atom.

14. A compound of the formula I

(I), wherein R and R1 are each independently of the other C1-C4alkyl, C1-C4alkoxy or hydroxy, X is hydrogen, halogen, C1-C4alkyl, C1-C4-alkoxy, trimethylsilyl, cyano, methoxycarbonyl or the radical -CH2-CH(NH2)-P(O)(R)(R1), and Y is hydrogen, halogen, C1-C2haloalk-oxy or C1-C2haloalkyl, or a salt thereof if R or R1 are hydroxy, with the proviso that at least one of the substituents X and Y has a meaning different from hydrogen if R and R1 are simultaneously hydroxy or ethoxy.

15. A compound of formula I according to claim 14 wherein R = R1 = OH;
X is hydrogen, fluorine, chlorine or bromine, C1-C4alkyl, CH3O, Si(CH3)3, -CN, -COOCH3 or -CH2-CH(NH2)-P(O)(OH)2, and Y is fluorine, chlorine, bromine, halomethoxy or halomethyl.

16. A compound of the formula I according to claim 15, wherein Y is, or contains, fluorine.

17. A compound of the formula I according to claim 14, wherein, R and R1 are each independently of the other C1-C4alkyl, C1-C4alkoxy or hydroxy, X is halogen, C1-C4alkyl, C1-C4alkoxy, Si(CH3)3, cyano or -CH2-CH(NH2)-P(O)(R)(R1), and Y is hydrogen, halogen, halomethoxy, haloethoxy or halomethyl.

18. A compound of the formula I according to claim 17, wherein X is fluorine, chlorine, methyl, ethyl, isopropyl, tert-butyl, methoxy, ethoxy, isopropoxy or cyano.

19. A compound of the formula I according to claim 14, wherein X is halogen, methyl, methoxy, or cyano, and Y is hydrogen, halogen, difluoromethoxy or trifluoromethyl.

20. A compound of the formula I according to claim 14, wherein X is hydrogen, and Y is difluoromethoxy or trifluoromethyl.

21. 1-Amino-2-(4-methoxyphenyl)ethanephosphonic acid.

22. 1-Amino-2-(4-fluorophenyl)ethanephosphonic acid.

23. 1-Amino-2-(2-chloro-4-fluorophenyl)ethanephosphonic acid.

24. A microbicidal composition which comprises an agriculturally acceptable carrier, and, as active ingredient, a compound of formula (I), wherein R and R1 are each independently of the other C1-C4alkyl, C1-C4alkoxy or hydroxy, X is hydrogen, halogen, C1-C4alkyl, C1-C4alkoxy, trimethylsilyl, cyano, methoxycarbonyl or the radical -CH2-CH(NH2)-P(O)(R)(R1), and Y is hydrogen, halogen, C1-C2haloalkoxy or C1-C2haloalkyl, or a salt thereof if R or R1 are hydroxy.

25. A composition according to claim 24 which contains a compound of formula I, wherein at least one of the substituents X
or Y has a meaning different from hydrogen, and R and R1 are simultaneously hydroxy or ethoxy.

26. A composition according to claim 24 which contains a compound of formula I, wherein R is C1-C4alkyl or OH, R1 is OH, X is hydrogen, halogen, C1-C4alkyl, C1-C4alkoxy, Si(CH3), -CN, -COOCH3 or CH2-CH(NH2)-P(O)(R)(R1), and Y is hydrogen, halogen, halomethoxy, haloethoxy or halomethyl.

27. A composition according to claim 26 which contains a compound of formula I, wherein R = R1 - OH, X is hydrogen, fluorine, chlorine or bromine, C1-C4alkyl, CH3O, Si(CH3)3, -CN, -COOCH3 or -CH2-CH(NH2)-P(O)(OH)2, and Y is fluorine, chlorine, bromine, halomethoxy or halomethyl.

28. A composition according to claim 27 which contains a compound of formula I, wherein Y is or contains, fluorine.

29. A composition according to claim 24 which contains a compound of formula I, wherein R and R1 are each independently of the other C1-C4alkyl, C1-C4alkoxy or hydroxy, X is halogen, C1-C4alkyl, C1-C4alkoxy, Si(CH3)3, cyano or -CH2-CH(NH2)-P(O)(R)(R1), and Y is hydrogen, halogen, halomethoxy, haloethoxy or halomethyl.

30. A composition according to claim 29 which contains a compound of formula I, wherein X is fluorine, chlorine, methyl, ethyl, isopropyl, tert-butyl, methoxy, ethoxy, isopropoxy or cyano.

31. A composition according to claim 24 which contains a compound of formula I, wherein X is halogen, methyl, methoxy or cyano, and Y is hydrogen, halogen, difluoromethoxy or trifluoromethyl.

32. A composition according to claim 24 which contains a compound of formula I, wherein X is hydrogen and Y is difluoromethoxy or trifluoromethyl.

33. A composition according to claim 24 which contains 1-amino-2-(4-methoxyphenyl)ethanephosphonic acid.

34. A composition according to claim 24 which contains 1-amino-2-(4-fluorophenyl)ethanephosphonic acid.

35. A composition according to claim 24 which contains 1-amino-2-(2-chloro-4-fluorophenyl)ethanephosphonic acid.