Decachlorooctahyro-1,3,4-metheno-2H-cyclobuta(c,d) pentalen-2-one prep - from hexachlorocyclopentadiene, and sulphur trioxide with antimony catalyst

摘要

Decachlorooctahydro-1,3,4-metheno-2H-cyclobuta(e,d) pentalen-2-one (I) is prepared by reacting SO3 with hexachlorocyclopentadiene in a mole ratio of 1.5 and 2 in the presence of Sb (III), Sn (V) halides, oxides or oxyacids as catalyst at 95-120 degrees C, and 50 to 300 psig. The reaction product is hydrolysed with 5 parts wt. aq. caustic alkali at pH >=9 at 85-115 degrees C for >=30 minutes, the pH adjusted to 5-6, with mineral acid, allowed to stand at 85-105 degrees C for 1 hour and the precipitated product (I) covered. (I) is an insecticide, particularly for controlling ants. and roaches. (I) is produced in 95% yields.