GB801523A - New phosphoric and acid thionophosphoric acid esters and a process for their production - Google Patents

Abstract

The invention comprises phosphoric and thionophosphoric acid esters of the general formula: <FORM:0801523/IV (b)/1> in which: <FORM:0801523/IV (b)/2> represents the residue of a cyclic dicarboxylic acid oximide, X is an oxygen or sulphur atom and R1 and R2 are alkyl radicals containing no more than 4 carbon atoms. They may be obtained by reacting a cyclic dicarboxylic acid oximide with a dialkyl phosphoric or thiophosphoric acid monohalide in the presence of an acid binding agent, e.g. an alkali metal carbonate or tertiary base or by reacting an alkali metal salt of a cyclic dicarboxylic acid oximide in the presence of a solvent with a dialkyl phosphoric or thiophosphoric acid monohalide. Specified solvents are methyl ethyl ketone, acetone and dimethyl formamide. Suitable reaction temperatures are between 0 DEG and 150 DEG C., e.g. between 20 DEG and 70 DEG C. Examples are given for the production of O,O-dimethyl-, O-O-diethyl-, ethyl n-propyl-, ethyl-isopropyl-and ethyl n-butyl-, phthalyl oximide thionophosphates; O,O-diethyl tetrachlorophthalyl oximide thionophosphate; O,O-diethyl phthalyl oximide phosphate; O,O-diethyl-D 4-tetrahydrophthalyl oximide thionophosphate; O,O-diethyl hexahydrophthalyl oximide thionophosphate; O,O - diethyl hexahydrophthalyl oximide thionophosphate; O,O - diethyl - 3,6-endomethylene - D 4 - tetrahydrophthalyl oximide thionophosphate; O,O - diethyl - 3,6-endomethylene - hexahydrophthalyl oximide thionophosphate; 1,2,3,4 - tetrahydronaphthalene - 1,4 - endo - oxy ethylene - 2,3 - dicarboxylic acid oximide thionophosphoric acid diethyl ester; O,O-diethyl naphthalic acid oximide thionophosphate and O,O-diethyl succinic acid oximide thionophosphate. Other cyclic oximide starting materials specified are dichlorophthalyl oximide; D 4-tetrahydronaphthyl oximide, and dichlorosuccinic acid oximide. The products are stated to have a low toxic effect against warm-blooded animals and to have pesticidal properties. Phthalyl oximide may be obtained by reacting hydroxylamine with phthalic anhydride and 1,2,3,4-tetrahydronaphthalene - 1,4 - endo - oxyethylene - 2,3-dicarboxylic acid oximide may be obtained by reacting b -naphthol and maleic anhydride to form 1,2,3,4 - tetrahydronaphthalene - 1,4-endo-oxyethylene-2,3-carboxylic acid anhydride which is then reacted with hydroxylamine to yield the oximide.