GB1087006A - Coumaranyl-carbamic acid esters and their use as insecticidal and acaricidal agents - Google Patents

Abstract

The invention comprises coumaranyl-carbamic acid esters of the general Formula I <FORM:1087006/C2/1> wherein R is hydrogen or a lower (up to C4) aliphatic hydrocarbon radical and R1, R2, R3 and R4, which may be the same or different are hydrogen or lower (up to C3) alkyl radicals. They are preferably prepared by reacting a compound of Formula II with an acid anhydride of the formula (RCO)2O, optionally in the presence of an inert organic solvent and generally at a temperature of 70-170 DEG C. An acidic catalyst, e.g. sulphuric or p-toluene sulphonic acid, may be present and the anhydride is preferably employed in an excess. The compounds may also be prepared (a) by reacting a compound of Formula II with the appropriate acid halide, (b) by reacting appropriate coumaranyl-chloroformic acid esters with appropriate acylamines, or (c) by reacting appropriate hydroxycoumaranes with appropriate N - methyl - N - acyl - carbamic acid chlorides. The compounds have insecticidal and acaricidal properties (see Division A5).ALSO:An insecticidal or acaricidal composition comprises a compound of the general formula: <FORM:1087006/A5-A6/1> where R is hydrogen or a lower (C1-4) aliphatic hydrocarbon radical and R1, R2, R3 and R4 which may be the same or different are hydrogen or lower (C1-3) alkyl radicals, and a solid or liquid diluent or carrier. The compounds which may be admixed with known active ingredients, may be employed in the form of solutions, emulsions, suspensions, powders, pastes or granules and the formulations generally contain between 0.1 and 95% by weight of the active compound. The formulations may be applied, e.g. by spraying, sprinkling, watering, scattering or dusting. The composition may also contain surface active agents, i.e. emulsifying and/or dispersing agents. The active compounds are suitable as insecticides and acaricides in plant protection and also for combatting hygiene pets.