Tandem rhodium catalysis: exploiting sulfoxides for asymmetric transition-metal catalysis.
نویسندگان
چکیده
Sulfoxides are uncommon substrates for transition-metal catalysis due to their propensity to inhibit catalyst turnover. In a collaborative effort with Ken Houk, we developed the first dynamic kinetic resolution (DKR) of allylic sulfoxides using asymmetric rhodium-catalyzed hydrogenation. A detailed mechanistic analysis of this transformation using both experimental and theoretical methods revealed rhodium to be a tandem catalyst that promoted both hydrogenation of the alkene and racemization of the allylic sulfoxide. Using a combination of deuterium labelling and DFT studies, a novel mode of allylic sulfoxide racemization via a Rh(III)-π-allyl intermediate was identified.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 13 21 شماره
صفحات -
تاریخ انتشار 2015