Diastereoselective Addition of Organometallics to Chiral α-Keto Amides Having trans-2,5-Disubstituted Pyrrolidine

Abstract

The nucleophilic addition of organotitanium reagents to α-keto amides derived from (2R,5R)-trans-2,5-bis(t-butyldimethylsiloxymethylsiloxymethyl)pyrrolidine [(R,R)-BTBSP] afforded the corresponding α-hydroxy amides with very high diastereofacial selectivity.

Stereochemical Control in Organic Synthesis Using Silicon-Containing Compounds

“…Diastereocontrol in reactions with aldehydes and ketones can be changed to enantiocontrol when a chiral auxiliary is attached by a temporary linkage, as in the reaction of allylsilanes on glyoxalates and pyruvates. A wide range of chiral auxiliaries has been tried, including those based on menthol, phenylmenthol, 2-phenylcyclohexanol, norephedrine, proline, , inositol, and 2,5-dihydroxymethylpyrrolidine, several of them with very high levels of selectivity. The homochiral auxiliary can also be an alcohol that generates an acetal in situ …”