| abstract |
A 1,1,1-trihalogeno-4-methyl-3-penten-2-ol is prepared by thermally isomerizing 1,1,1-trihalogeno-4-methyl-4-penten-2-ol. The isomerization reaction may be catalyzed by an acid or a transition metal of Group 6B, 7B or 8 of the Periodic Table of Elements, or a compound thereof. The 1,1,1-trihalogeno-4-methyl-3-penten-2-ol thus prepared is useful as a synergist for herbicides or a physiologically active compound, and, additionally, is useful as a starting material for the synthesis of 2,2-dimethyl-3-(2',2'-dihalogenovinyl)-cyclopropane carboxylic esters which are active ingredients of insecticides. |