1, 1-DISUBSTITUTED-4-UNSUBSTITUTED- OR 1, 1-DISUBSTITUTED- 4-ALKYL-SUBSTITUTED-BUTADIENE-1, 3 AND ITS PREPARATION

摘要

NEW MATERIAL:The 1, 1-disubstituted-4-unsubstituted- or 1, 1-disubstituted-4- alkyl-substituted-butadiene-1, 3 of formulaI(R1 is alkyl, cyclohexyl which may be substituted with halogen, or OH; R2 is H or lower alkyl; R3 is saturated or unsaturated lower alkyl or benzyl which may be substituted with lower alkyl). EXAMPLE:5-Benzyl-5, 7-octadien-4-one. USE:Starting raw material for the preparation of carotenoid, prostaglandin, etc. Fungicide and insecticide in the pharmaceutical, agricultural and horticultural fields. PROCESS:The compound of formulaIcan be prepared by the thermal decomposition of the 2, 2-disubstituted-5-unsubstituted- or 2, 2-disubstituted-5-alkyl-substituted-2, 5-dihydrothiophene-1, 1-dioxide of formula II.