GB901880A - New pentafluorobenzene derivatives and processes for their manufacture - Google Patents

Abstract

The invention comprises compounds of the formula <FORM:0901880/IV (b)/1> where R1 represents hydrogen or a C1-C4 alkyl radical, R2 represents hydrogen or a cyano or carboxamido radical or a radical COOR where R is hydrogen or a C1-C4 alkyl group and R3 represents a cyano or carboxamido radical or a radical COOR where R is as defined above together with a process for their preparation by interacting hexafluorobenzene with a compound M.CR1R2R3 where M represents a metal of Group I of the Periodic system. Compounds in which R1 is alkyl may be prepared by alkylating compounds in which R1 is hydrogen and cyano, acid, ester and amide or radicals in the products may be converted one to the other by the usual methods. Examples describe the preparation of diethyl a -pentafluorophenylmalonate and its a -ethyl derivative, a -pentafluorophenylmalonodinitrile and its a -ethyl derivative, ethyl a - pentafluorophenylcyanacetate, t.butyl a -pentafluorophenylcyanacetate, a - ethyl - a - pentafluorophenylmalonodiamide, pentafluorophenylacetic acid and its amide. Pentafluorophenylacetyl chloride is prepared from the acid. The Provisional Specifications refer more generally to compounds of the above formula where R1 represents a nitro, cyano, aldehyde or carboxy radical or a radical of the formula SO2R4, SO2NR4R5, COR4, COOR4, CONR4R5, COOCOR4, NR4COR5 or N(COR4)COR5 where R4 and R5 stand for hydrogen or hydrocarbon radicals which may be substituted or R4 and R5 may be formed together to form a divalent hydrocarbon radical; and R2 and R3 which may be the same or different represent hydrogen or hydrocarbon radicals which may be substituted or any of the values specified for R1.