| 摘要 |
A process for preparing bicyclic 1,3-diketones of the formula IwhereR<1>, R<2>, R<3 >and R<4 >are hydrogen, C1-C4-alkyl, C1-C4-alkoxy-carbonyl, halogen, cyano, nitro, C1-C4-alkylthio, C1-C4-alkylsulfenyl or C1-C4-alkylsulfonyl andZ is C1-C4-alkylene, O, S, N-R<5 >whereR<5 >is C1-C4-alkyl or C1-C4-alkylcarbonyl,which comprisesa) reacting a bicyclic olefin of the formula II with haloform in the presence of a base to give the ring-expanded product of the formula IIIwhereR<1>-R<4 >and Z are as defined above andX is halogen;b) hydrolyzing the allylic halogen of the compound of the formula III to the allyl alcohol of the formula IVc) oxidizing the allyl alcohol of the formula IV to the unsaturated ketone of the formula Vd) reacting the ketone of the formula V with a nucleophilic ion Y<-> which stabilizes a negative charge to give the ketone of the formula VIe) hydrolyzing the ketone of the formula VI to the bicyclic 1,3-diketone of the formula I,novel intermediates and novel processes for preparing these intermediates are described. |
