PROCESS FOR PREPARING PESTICIDE COMPOUNDS 1-PHENYL-2,2-DIHALO-ETHANOL DERIVATIVES

摘要

1,229,992. 1 - Phenyl - 2,2 - halogenoethanol derivatives. ROUSSEL UCLAF. 18 July, 1968 [18 July, 1967; 6 June, 1968], No. 34399/68. Heading C2C. [Also in Division A5E] The invention comprises compounds of the Formula I wherein X 1 and X 2 represent a hydrogen or halogen atom or a substituted or unsubstituted lower alkyl C 1-4 or lower alkoxy C 1-4 group and X 2 in addition represents a nitro group, X 3 and X 4 represent a hydrogen or halogen atom, Y represents a hydrogen atom, a lower alkyl C 1-4 or lower acyl C 1-4 group or the residue of a mineral acid, Z represents a hydrogen atom or a lower alkyl C 1-4 group and Hal represents a chlorine, bromine or iodine atom provided that when the groups Hal represent chlorine atoms, Y and Z each represent a hydrogen atom and one of X 1 -X 4 represents a hydrogen or chlorine atom, the remainder of X 1 -X 4 do not all represent hydrogen atoms. They are prepared by reduction of the corresponding ketone of Formula II to produce a compound of Formula I wherein Y = H and reacting this further with alkylating or acylating agents or mineral acids as desired. The reduction of a ketone III may be carried out using an aluminium alcoholate e.g. the isopropoxide and a secondary alcohol e.g. isopropanol or by reaction with a metal borohydride or hydrogen and/or a platinum catalyst. In an example 1 - acetoxy - 1 - (21,51 - dichlorophenyl) - 2,2 - dichloroethane is prepared by reacting 1 - (21,51 - dichlorophenyl) - 2,2- dichloroethanol with acetic anhydride; 1- ethoxy - (21,51 - dichlorophenyl) - 2,2 - dichlorethane is prepared from the corresponding alcohol and triethyloxonium fluoroborate. The following compounds of Formula I are prepared by reduction of the corresponding ketone: 1- (21,51- or 21,41- or 31,4-dichlorophenyl)-2,2- dichloroethanol, 1 - (21 - methoxy - 51 - chlorophenyl)- or 1 - (21,51 - dibromophenyl)- or 1- (41 - nitrophenyl)- or 1 - (21 - chloro - 51 - nitrophenyl) - 2,2 - dichloroethanol, 1 - (21- chlorophenyl) - 2,2 - dichloropropanol and 1 - (21,51- dichlorophenyl) - 2,2 - dibromoethanol. The ketones of Formula II may be prepared by direct halogenation of a ketone of Formula III or by the reaction of a compound of Formula IV with a halide of an acid of formula 21 - Chloro - 51 - methylacetophenone is prepared by reacting 4-chlorotoluene with acetyl chloride. The following ketones of Formula II are prepared: 2,2,21,41,51 - , 2,2,21,31,41 - pentachloroacetophenone, 2,2,21,41 - tetrachloroacetophenone, 2,2 - dichloro - 21,51 - dibromoacetophenone, 2,2,21 - trichloropropiophenone, 2,2,21 - trichloro - 51 - nitroacetophenone, 2,2,21 - trichloro- 51 methylacetophenone and 21 - methoxy- 2,2,51 - trichloroacetophenone. The compounds of Formula I have insecticidal and/or herbicidal activity.