By using complementary and selectively acting reagents (TiCl4 and sulfurane 16), azafrin, the main carotenoid in the rhizomes of Escobedia scabrifolia, has been shown to have the (5R:6R)-configuration. Reaction of azafrinaldehyde (4) with (Ph3P)3RhCl leads to a mixture of 5 and 6, the latter arising probably through elimination of acetylene and recarbonylation.
通过使用互补和选择性作用的试剂(TiCl 4和
硫烷16),已证明sc草素(Escobedia scabrifolia)的根状茎中的主要类
胡萝卜素具有(5 R:6 R)-构型。氮杂品醛(4)与(Ph 3 P)3 RhCl的反应生成5和6的混合物,后者可能是通过消除
乙炔和重新羰基化而产生的。