Tandem α-Alkylation/Asymmetric Transfer Hydrogenation of Acetophenones with Primary Alcohols
作者:Oleksandr O. Kovalenko、Helena Lundberg、Dennis Hübner、Hans Adolfsson
DOI:10.1002/ejoc.201403032
日期:2014.10
A tandem -alkylation/asymmetric transferhydrogenation of acetophenones with primary alcohols, mediated by a single ruthenium catalyst, is described. Under optimized reaction conditions and with use of [Ru(p-cymene)Cl-2](2) in combination with an amino acid hydroxyamide ligand, the chiral secondary alcohol products were isolated in moderate yields and in moderate to good enantiomeric excess (up to
An efficient catalyst for the asymmetric addition of organoaluminum reagents to aldehydes is presented. The system is based on a readily available binaphthyl derivative as a chiral ligand and an excess of titanium tetraisopropoxide. The asymmetric methylation, ethylation, and propylation of a wide variety of aromatic and aliphatic aldehydes proceeded with good yields and with high enantioselectivities in a simple one-pot procedure under mild conditions. (C) 2012 Elsevier Ltd. All rights reserved.