Herein an operationally simple alkylation of methylene ketones with primary alcohols is reported. Use of an inexpensive and earth abundant Mn/1,10-phenanthroline system enables direct access to a series of functionalised branchedketones including one-pot sequential double alkylation and Alzheimer's drug donepezil. Preliminary mechanistic investigation, determination of the rate and order of reactions
By employing an easily available [Ru(p-cymene)Cl-2](2)/Xantphos/t-BuOK catalyst system, the alpha-alkylation of ketones was demonstrated by using pyridyl methanol as the alkylating reagents. The synthetic protocol allows synthesizing a wide range of alpha-pyridyl methylated ketones in reasonable to excellent isolated yields with high atom-efficiency. The transformation is operationally simple, the substrate scope is wide, and the starting materials are readily-available. There is no need for addition of alkenes as the hydrogen receptors or the use of stoichiometric amount of base. (C) 2013 Elsevier Ltd. All rights reserved.