Stoichiometric and catalytic reductive aldol cyclizations of alkynediones induced by Stryker's reagent.
نویسندگان
چکیده
Conjugate reduction of alkynones by stoichiometric [(Ph(3)P)CuH](6) or catalytic [(Ph(3)P)CuH](6) and polymethyl-hydrosiloxane proceeds to cyclization by an aldol reaction with tethered ketones to generate [small beta]-hydroxyenones with good diastereoselectivity.
منابع مشابه
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A range of enethioate derivatives of 1,3-diones underwent reductive aldol cyclizations catalyzed by a chiral copper hydride generated in situ from 5 mol% TaniaPhos (SL-T001-1), 5 mol% Cu(OAc)(2)·H(2)O, 5 mol% bipyridine and 2.0 equiv. of PhSiH(3), to furnish polycyclic β-hydroxythioester products bearing three newly established contiguous stereocenters, with >98:2 dr and in up to 94% yield and ...
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ورودعنوان ژورنال:
- Chemical communications
دوره 20 شماره
صفحات -
تاریخ انتشار 2004