Direct trapping of sterically encumbered aluminum enolates

Org Lett. 2013 May 3;15(9):2152-5. doi: 10.1021/ol400642y. Epub 2013 Apr 22.

Abstract

The formation of chiral and sterically congested cyclohexanone derivatives has been achieved through a multistep sequence with one single purification step. (n-Butoxymethyl)-diethylamine was identified as a highly efficient reagent for the direct trapping of aluminum enolates. The Lewis acidic character of aluminum suffices to activate the α-aminoether to form in situ an electrophilic iminium species. In return the aluminum enolate is rendered more nucleophilic by coordination of the butoxy group and formation of an aluminate.