Synthetic studies towards complex diterpenoids-171: synthesis and oxidative cleavage of ()-19,20-cycloabieta-19-oxo-8,11,13-triene
作者:Bimal K. Banik、Usha Ranjan Ghatak
DOI:10.1016/s0040-4020(01)81033-4
日期:1989.1
Oxidative cleavage of the enolates of ()-19,20-cycloabieta-19-oxo-8,11, 13-triene () and the related tetracyclic ketone () with molecular oxygen leads to ()-abieta-8,11,13-triene-19,20-dioic acid () and the dicarboxylic acid () respectively. The synthesis of the tetracyclic ketone () has been realized by two different methods through Ni(acac)2 catalyzed intramolecular carbon-hydrogen insertion of the
()-19,20-cycloabieta-19-oxo-8,11,13-三烯()和相关的四环酮()的烯醇被分子氧氧化裂解,导致()-abieta-8,11,13 -三烯-19,20-二甲酸()和二羧酸()。四环酮()的合成已通过两种不同的方法,通过Ni(acac)2催化由()-20-nor-4-epidehydroabietic acid()内酯和环丁酮()的立体特异性重排,得自易于获得的不饱和酸()不饱和环丁烯酮()。锂氨还原仅生成()-20-去脱氢松香酸(),而Pd-C(10%)以上的催化氢化导致A / B环顺式酸()作为主要产物。在相同条件下,通过氢解仅从内酯中获得β-内酰胺。