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

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.