Stoichiometric and catalytic reductive aldol cyclizations of alkynediones induced by Stryker's reagent
作者:Pauline Chiu、Sze Kar Leung
DOI:10.1039/b407842j
日期:——
Conjugate reduction of alkynones by stoichiometric [(Ph3P)CuH]6 or catalytic [(Ph3P)CuH]6 and polymethyl-hydrosiloxane proceeds to cyclization by an aldol reaction with tethered ketones to generate β-hydroxyenones with good diastereoselectivity.
[see reaction]. Conjugate reduction by Stryker's reagent to form copper enolates, followed by intramolecular aldol cyclization, successfully generated five- and six-membered carbocycles in one pot efficiently. This tandem reaction is generally diastereoselective and provides good yields of the beta-hydroxyketones without any dehydration at low temperatures.