Preparation of 2-(2-hydroxyphenyl)-2-(alkoxyimino)-N-alkylacetamide derivatives useful as intermediates for pest control agents comprises chlorinating a fused enol acetate derivative, ring opening and derivatizing

摘要

Method for the preparation of 2-(2-hydroxyphenyl)-2-(alkoxyimino)-N-alkylacetamide derivatives (I). Method for the preparation of 2-(2-hydroxyphenyl)-2-(alkoxyimino)-N-alkylacetamide derivatives of formula (I) comprises: (a) treating an enol acetate of formula (IV) with chlorine (Cl2) gas optionally in presence of a diluent; (b) treating the dichloro product of formula (V) with an amine of formula R1NH2 (or its acid addition complex) optionally in presence of a diluent and/or acid acceptor; and (c) then either: (1) treating the ring-opened product of formula (VI) with hydroxylamine (or acid addition complex) optionally in presence of a diluent and/or buffer to give a hydroxy compound which is then alkylated with R2-X (where X = halogen, -O-CO-O-R2, -O-SO2-R2 or -O-SO2-O-R2) optionally in presence of a diluent and/or acid acceptor and/or phase transfer catalyst to give (I); or (2) treating the ring-opened product of formula (VI) with an alkoxyamine of formula R2-O-NH2 (or acid addition complex) optionally in presence of a diluent and/or buffer and/or acid acceptor to give (I). R1, R2 = 1-4C alkyl, except in the novel compounds (III) where R1 = 1-4C alkyl and R2 = 2-4C alkyl. Independent claims are also included for: (1) the preparation of 2-(2-hydroxyphenyl)-2-(alkylimino)-N-alkylacetamide derivatives of formula (VI); and (2) novel compounds of formula (I), where R1 = 1-4C alkyl and R2= 2-4C alkyl.