Stereoselectivity of the benzannulation reaction: efficient central-to-axial chirality transfer.
نویسندگان
چکیده
High diastereoselectivity is observed in the preparation of configurationally stable allocolchicinoids 5 from Fischer carbene complexes 4 and 1-pentyne. The analogous reaction of complexes 8 gives 9 with moderate diastereoselectivity for the opposite atropisomer and this selectivity can be taken to high levels under thermodynamic conditions.
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ورودعنوان ژورنال:
- Journal of the American Chemical Society
دوره 124 23 شماره
صفحات -
تاریخ انتشار 2002