A 4-cyclopentenone of the formula: ##STR1## wherein R is a lower alkyl group, a lower alkenyl group or a lower alkynyl group and R' is a hydroxyl group or an aliphatic acyloxy group, provided that in case of the dl-form, R' is not a hydroxyl group and also that the substituent R at the 2-position and the methyl group at the 3-position take a cis-configuration in the dl-, d- or l-form.
A process for producing a compound of the formula: ##STR1## wherein R.sub.1 is a hydrogen atom, an alkyl group or an alkenyl group and R.sub.2 is an alkyl group, an alkenyl group or an alkynyl group, which comprises treating a compound of the formula: ##STR2## wherein R.sub.1 and R.sub.2 are each as defined above and R is a hydrogen atom or a lower alkyl group in the presence of an acidic substance and water.
A 4-cyclopentenone of the formula:
wherein R is a lower alkyl group, a lower alkenyl group or a lower alkynyl group and R' is a hydroxyl group or an aliphatic acyloxy group, provided that in case of the dℓ-form, R' is not a hydroxyl group and also that the substituent R at the 2-position and the methyl group at the 3-position take a cis-configuration in the dℓ-, d- or ℓ-form.
式中 R 为低级烷基、低级烯基或低级炔基,R'为羟基或脂肪酰氧基的 4-环戊烯酮,但在 dℓ-形式中,R'不是羟基,并且在 dℓ-、d- 或 ℓ-形式中,位于 2 位的取代基 R 和位于 3 位的甲基呈顺式构型。
Optically active 4-hydroxy-2-cyclopentenones, and their production
申请人:SUMITOMO CHEMICAL COMPANY, LIMITED
公开号:EP0115860A2
公开(公告)日:1984-08-15
A process for preparing an optically active 4-hydroxy-2- cylopentenone of the formula:
wnerem R1 is a nyarogen atom or a methyl group, R2 is an alkyl group, an alkenyl group or an alkynyl group and the asterisk (*) indicates an asymmetric configuration, which comprises subjecting an optically active 4-cylopentenone-alcohol of the formula:
wherein R1 and R2 are each as defined above, the asterisk (*) indicates an asymmetric configuration and the substituents R1 and R2 take a cis-configuration to rearrangement while maintainig the original steric configuration.