stereochemically defined 1,6-enyne dicobalt hexacarbonyl complexes (12, 13) that undergo highly diastereoselective intramolecular Pauson-Khand cyclizations to bicyclooctenones 14 and 15 (90% e.e. for 15). The mechanistically significant reversal of enantioselectivity in the allylborations of 10 compared to the parent 3-decynal 5 is also reported.
3-癸
二乙基二羰基二羰基(10)的对映选择性
巴豆基
硼酸酯为立体
化学定义的1,6-烯炔
二乙基六羰基复合物(12、13)提供了一条非常便捷的途径,该化合物经历了高度非对映选择性的分子内Pauson-Khand环化成双环
辛烯酮14和15(90%) ee 15)。还报道了与母体3-
癸醛5相比,烯丙基
硼化10中的对映选择性的机械上显着的逆转。