CS268161B2 - Process for preparing 2,3-dihydro-2,2-dimethylbenzofuran-7-n-/n,n-disubstituted aminosulphenyl/-n-methylcarbamate - Google Patents

Abstract

Aminosulphenyl cpds. of formula R1R2NSCl (I) are new. R1 and R2 are X.COOR3 or YCN, or R2 can also be 1-8C alkyl, 3-6C cycloalkyl, phenyl or benzyl (both opt. substd. by halo, or 1-3C alkyl or alkoxy or ZR4. X and Y as 1-6C alkylene. R3 is 1-8C alkyl or 3-6C cycloalkyl. Z is carbonyl or sulphonyl. R4 is 1-6C alkyl, phenyl (opt. substd. by halo or 1-3C alkyl or alkoxy)or phenoxy. - (I) are prepd. e.g. by reacting R1R2NM with sulphur mono- or di-chloride. - (I) are intermediates for cpds.

Description

(57) A process for the preparation of 2,3-dihydro-2,2-dimethylbenzofuran-7-yl-N- (N, N-disubstituted aminosulfenyl) -N-methylcarbamate of the general formula III, wherein each of R ¹ and R 2 which are identical or different, (1) represents a group of the formula - X - COOR, wherein X represents an alkylene group having 1 to 6 carbon atoms and R ^? C 1 -C 8 alkyl or C 3 -C 6 cycloalkyl; or (2) a group of the formula - Y - CN wherein Y represents alkylensku-yne containing 1-6 carbon atoms and R ^z furthermore is an alkyl radical containing 1 to 8 carbon atoms; (C 3 -C 6) cycloalkyl; benzyl optionally substituted with halogen, C 1 -C 3 alkyl or C 1 -C 3 alkoxy; phenyl optionally substituted with halogen, C 1 -C 3 alkyl or C 1 -C 3 alkoxy; or a group of the formula - Z - R ⁴ , wherein Z is a carbonyl or sulfonyl group and R ⁴ is a C 1-6 alkyl group, a phenyl group optionally substituted by a C 1 -C 3 alkyl group or a halogen atom, a C 1 -C 3 alkoxy group carbon atoms or phenoxy, characterized in that the aminosulfenyl chloride derivative of the general formula I

Wherein R and R are as defined above, reacted in the presence of a base at -20 to 50 ° C with 2,3-dihydro-2,2-dimethylbenzofuran-7-yl-N-methylcarbamate of formula II.

(II)

CS 268 161 82

The present invention relates to a process for the preparation of carbamates having an insecticidal activity using novel aminosulfenyl chloride derivatives. The term insecticidal effect and the like in these substrates, unless otherwise indicated, includes also the acaricidal effect and does not have a tocid effect in addition to the normal insecticidal effect. The term insects, unless otherwise indicated, is also understood in a broader sense and includes mites and nematodes in addition to the insects themselves.

In the prior art there is described 2,1-dihydro-2,2-dimethylbenzofuran-7-yl-1H-methylcarbamate (known as carbofuran) of formula II

Carbofuran alone is known to have the highest insecticidal activity known so far of known carbamates, but its use causes problems in practical use because it has a high toxicity to warm-blooded animals. It has now been found in the context of the invention that by reacting carbofuran with certain aminosulfenyl chloride derivatives it is possible to obtain compounds having insecticidal activity, i.e. a control effect against agricultural and forest insect pests and against domestic insect pests, comparable to that of carbofuran but its toxicity against warm-blooded animals is only about 1/5 to about 1/100 of carbofuran toxicity.

The present invention provides a process for the preparation of 2,1-dihydro-2,2-dimethylbenzofuran-7-yl-N- (Ν, Ν-disubstituted aminosulfenyl) -N-methylcarbamate of formula III

Wherein each of R and R, which are of the formula - X - COOr, wherein X is and R 1 is an alkyl group containing 1 identical or different, (1) is a C 1 -C 6 alkyl group and a carbon atom of up to 8 carbon atoms or a C 1-6 alkyl group; or (2) a group of the general formula

Y - Cf 1 wherein Y is CS 268 161 B2 is an alkylene group having 1 to 6 carbon atoms; and R furthermore represents an alkyl group having 1 to 8 carbon atoms; and cycloalkyl having 3 to 6 carbon atoms; benzyl optionally substituted with halogen, C 1 -C 3 alkyl or C 1 -C 3 alkoxy; phenyl optionally substituted with halo, C 1 -C 3 alkyl or C 1 -C 3 alkoxy; or a group

Wherein Z is carbonyl or sulfonyl and R is C 1 -C 6 alkyl, phenyl optionally substituted by C 1 -C 3 alkyl or halo, C 1 -C 3 alkoxy or a phenyloxy group, characterized in that the amino sulfonylphenyl derivative of the general formula (I).

Wherein R and R are as defined above, reacted in the presence of a base at a temperature of (I)

-20 to 50 ° C with 2,3-dihydro-

The compounds of formula (I) are novel compounds which can be prepared by a variety of methods, of which the following methods 1 and 2 are preferred.

Method 1

The compounds of formula (I) can be readily obtained by reacting the ainin major and the formula (IV)

Him

where

2

R and R are as defined above,

CS 268 161 02 with sulfur trichloride or sulfur trichloride, as illustrated in equations 1 and 2

with ₂ ei ₂ \

-> N - S - Cl f S + HCl (1) /

'2

(2)

2

In the above reactions 1 and 2, R and R are as defined above.

Both reaction 1 using sulfur trichloride and reaction 2 using sulfur trichloride can be carried out within a short time. Reaction 1 releases sulfur. Both reactions proceed under the same conditions and can be carried out optionally in the presence of a solvent. Examples of solvents that may be used include halogenated hydrocarbons such as methylene chloride, chloroform, carbon tetrachloride, dichloroethap, trichlorethylene, methyl chloroform, etc .; ethers such as diethyl ether, dipropyl ether, dibutyl ether, tetrahydrofuran, dioxane etc .; hydrocarbons such as n-pentane, n-hexane, n-heptane, cyclohexane, etc .; and aromatic hydrocarbons such as benzene, toluene, xylene, chlorobenzene, etc. The ratio of the amount of the compound of formula (IV) to sulfur trichloride or sulfur trichloride is not particularly limited and can be varied within wide limits. Usually 1 to 2 moles, preferably 1 to 1.2 moles of sulfur chloride are used per mole of the compound of formula (IV). The reaction is preferably carried out in the presence of a basic compound. Examples of basic compounds which may be used include tertiary amines such as triethylamine, tributylamine, dimethylaniline, diethylaniline, ethylmorpholine, etc .; and pyridines such as pyridine, picoline, lutidine, etc. The basic compounds can be used in an amount sufficient to capture the hydrogen chloride to be released as a by-product in the reaction. Usually about 1 to about 2 moles, preferably about 1 to 1.5 moles, of a basic compound per mole of the compound of formula (II) are used. The reaction may be carried out with cooling, at room temperature or with heating. Usually it is operated at a temperature of from -20 to about 50 ° C, and preferably from -10 to 30 ° C. The reaction time ее varies depending on the basic compound used, but is usually about 1 to about 2 hours.

Method 2

Compounds of formula (I) are also readily obtainable by reacting a compound of formula (IV) with sulfur trichloride to give the oisaminodisulfide derivative of formula (V).

CS 268 161 02

2 wherein R and R are as described above, after which the chlorination is carried out. The procedure is illustrated by reactions 3 and 4

NH + S ₂ Cl ₂ --------> / _2 R R ¹ R ¹ \ / -> N - S - S - N + 2HCl (3) / \ ₂ N R ²

Reaction 3 may be carried out optionally in the presence of a solvent or in a two-phase system consisting of solvent and water. Examples of solvents that may be used include halogenated hydrocarbons such as methylene chloride, chloroform, carbon tetrachloride, dichloroethane, trichlorethylene, methyl chloroform, etc .; ethers such as diethyl ether, dipropyl ether, dibutyl ether, tetrahydrofuran, dioxane, etc .; hydrocarbons such as n-pentane, n-hexane, n-heptane, cyclohexane, etc .; and aromatic hydrocarbons such as

CS 260 161 02

Claims (4)

benzene, toluene, xylene, chlorobenzene, etc. In reaction 3, the ratio of the amount of the compound of formula (IV) to the sulfur trichloride is not particularly limited and can be varied within a relatively wide range. Typically, about 0.5 moles of sulfur trichloride is used per mole of compound of formula IV. Reaction 3 is preferably carried out in the presence of a basic compound. The basic compounds used may be amino compounds which serve as starting materials. Other examples of basic compounds include tertiary amines such as triethylamine, lamin tributy, dimethylamine, diethylamine, ethylmurfoline, etc .; and pyridines such as pyridine, picoline, lutidine, etc. When, in contrast, the reaction is carried out in a two-phase system consisting of solvent and water, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate etc. can be used as the basic compound. may be used in an amount sufficient to contain the hydrogen chloride to be released as a by-product in the reaction. Usually about 1 to about 10 moles, preferably 1 to 5 moles, of a basic compound per mole of the compound of formula (IV) are used. The reaction may be carried out with cooling, at room temperature or with heating. It is generally carried out at a temperature of from -20 to about 50 ° C, preferably from 0 to 40 ° C. The reaction time varies depending on the basic compound used, but is usually about 1 to about 2 hours. The bisaminodisulfide derivative of formula (V) thus obtained can be purified and then used, or the reaction solution can be washed with water, dried and then used directly for the next reaction. Reaction 4 may optionally be carried out in the presence of a solvent. Any suitable solvents for the reaction may be used 3. Examples of chlorinating agents that may be used include chlorine, sulfuryl chloride, etc. The ratio of the amount of the compound of formula (V) to the chlorinating agent is not particularly limited, and can be varied within a relatively wide range. Typically, about 0.5 to about 5 moles, preferably 0.5 to about 1.5 moles, of chlorinating agent are used per mole of compound of formula (V). The reaction may be carried out with cooling, room temperature or heating. Generally, the temperature is from -20 to about 50 ° C, preferably ad -10 to 30 ° C. The reaction is complete in about 1 to about 2 hours. The amino compounds of formula IV are known compounds. Examples of useful amino compounds of formula IV include the secondary amines of general formula VI to X ¹ HN CS 268 161 82 CN (VII) X - COOR ³ FROM HN X - COOR ³ COOR ³ (IX) CN (X) In formulas VI to X, Y, Y and R a are as defined above, R is C 1 -C 8 alkyl; (C 3 -C 6) cycloalkyl; a benzyl group optionally substituted by a halogen atom, an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms; a phenyl group optionally substituted by a halogen atom, a (C 1 -C 3) alkyl group or a (C 1 -C 3) alkyl group. 4. Or (2 - R) wherein 2 is carbonyl R 4 is C 1 -C 6 alkyl, phenyl, benzyl, C 1 -C 6 alkoxy or phenoxy (in which alkyl may be irium and η 1 may be straight or branched chain); R ³ has the same meaning as \ X 'has the same meaning as X and Y ”has the same meaning as Y. Representative examples of amino compounds of formula (VI) are N-methylglycine methyl ester, N-methylglycine ethyl ester, N-methylglycine butyl ester, N-ethylglycine ethyl ester, N-n-nitroglycol glycine ethyl ester, N-isopropylglycine ethyl ester, N-n-butylglycine ethyl ester, N-isobutyl ester CS 266 161 02 ethyl ester of N-sec-butylglycine ethyl ester of N-octylglycine ethyl ester of N-cyclohexylglycine ethyl ester of N-benzyiglycine ethyl ester of N- (4-methylbenzyllglycine ethyl ester of N- (4-chlorobenzyl) glycine ethyl ester of N-phenylglycine ethyl ester of N-) glycine N- (4-methoxyphenyl) glycine ethyl ester N-methoxycarbonylglycine ethyl ester N-ethoxycarbonylglycine ethyl ester N-ethoxycarbonylglycine ethyl ester N-ethoxycarbonyl glycine ethyl ester N-phenoxycarbonylpropyl amine ethyl ester N-phenoxycarbonyl glycoline N-isopropylaminopropionate butyl-N-isopropylaminopropionate 2-ethylhexyl-N-isopropylaminopropionate methyl-N-butylaminopropionate ethyl-N-butylaminopropionate ethyl-N-isobutyl amine N-sec-butylaminopropionate 1-Ni soamy laminopropionate