Enantioselective Photochemical Organocascade Catalysis
نویسندگان
چکیده
Reported herein is a photochemical cascade process that combines the excited-state and ground-state reactivity of chiral organocatalytic intermediates. This strategy directly converts racemic cyclopropanols and α,β-unsaturated aldehydes into stereochemically dense cyclopentanols with exquisite stereoselectivity. Mechanistic investigations have enabled elucidating the origin of the stereoconvergence, which is governed by a kinetic resolution process.
منابع مشابه
Enantioselective total synthesis of (-)-minovincine in nine chemical steps: an approach to ketone activation in cascade catalysis.
Dressed to the nines: The first enantioselective total synthesis of (-)-minovincine has been accomplished in nine chemical steps and 13 % overall yield. A novel, one-step Diels-Alder/β-elimination/conjugate addition organocascade sequence allowed rapid access to the central tetracyclic core in an asymmetric manner. Boc=tert-butoxycarbonyl, LG=leaving group, PMB=para-methoxybenzyl.
متن کاملCycle-Specific Organocascade Catalysis: Application to Olefin Hydroamination, Hydro-oxidation, and Amino-oxidation, and to Natural Product SynthesisFinancial support was provided by the NIHGMS (R01 GM078201-01-01), Merck, and Amgen. B.S. is grateful for a Merck predoctoral fellowship
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