Copper-Catalyzed Enantioselective Conjugate Addition of Grignard Reagents to Acyclic Enones
作者:Fernando López、Syuzanna R. Harutyunyan、Adriaan J. Minnaard、Ben L. Feringa
DOI:10.1021/ja046632t
日期:2004.10.1
A highly enantioselective Cu-catalyzed addition of Grignard reagents to acyclic aliphatic enones is described. In the presence of 5 mol % of CuBr.SMe2 and 6 mol % of JosiPhos diphosphine aliphatic enones react with Grignard reagents to provide beta-substituted linear ketones with high yields, regio-, and enantioselectivities.
The present invention provides a process for the oxidation of straight-chain, branched-chain or cyclic alkanes of 1-20 carbon atoms and benzene derivatives represented by the following formulas (1) - (2). The alcohols and ketones obtained by the oxidation of the alkanes mentioned above and those by the oxidation of the benzene derivatives mentioned above represented by the following formulas (3) - (6) are important as basic starting materials in producing various chemical products including resins, such as nylon and polyester, pharmaceuticals, agricultural chemicals, perfumes, dyes, etc.
The Michael-type reaction of copper-catalyzed trialkylaluminium reagents with α,β-unsaturated carbonylcompounds is a useful and simple procedure for the transfer of hydrocarbon substituents. The scope of this process and the effect of chlorotrimethylsilane as additive were investigated. Preparatively useful results were generally obtained for enones even with higher organoaluminium reagents, whereas