Stereoselective synthesis of silicon-stereogenic aminomethoxysilanes: easy access to highly enantiomerically enriched siloxanes

Angew Chem Int Ed Engl. 2014 Jan 13;53(3):720-4. doi: 10.1002/anie.201307826. Epub 2013 Dec 2.

Abstract

A route towards the synthesis of N,O-functionalized silicon-stereogenic organosilanes with excellent optical purities has been developed. Investigations into the stereoconvergence and configurational stability of an aminomethoxysilane suggest a kinetically controlled multistep substitution mechanism. Selective exchange of the Si-N bond by a second Si-O bond builds the basis for the controlled formation of chiral siloxane units with different oxygen-containing functional groups. Subsequent reactions of the chiral aminomethoxysilanes with hydroxy groups support a general inversion mechanism at the asymmetrically substituted silicon atom of N,O-functionalized organosilanes.

Keywords: aminomethoxysilanes; chiral siloxanes; diastereoselectivity; silicon; substitutions.