Asymmetric homogeneous hydrogenation of 2,5-disubstituted furans.
نویسندگان
چکیده
A homogeneous catalyst system for the asymmetric cis-hydrogenation of 2,5-disubstituted furans leading to 2',3'-dideoxynucleoside analogues is described. Best enantioselectivities (ee values of up to 72%) were obtained with cationic rhodium complexes ligated by diphospholanes of the butiphane family. The selectivity of the hydrogenation was reversed by the addition of a base or a polar protic solvent in certain cases. Ferrocene- and proline-based systems gave significant, but lower, ee values.
منابع مشابه
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ورودعنوان ژورنال:
- Organic letters
دوره 8 18 شماره
صفحات -
تاریخ انتشار 2006