Cyclization via carbolithiation of alpha-amino alkyllithium reagents.
We report a new route to tertiary alpha-amino stereocenters by sequential alkylation of alpha-amino nitriles followed by reductive lithiation of the nitrile and cyclization onto an alkene. Reductive lithiation of alpha-amino nitriles using lithium 4,4'-di-tert-butylbiphenylide (LiDBB) and subsequent intramolecular carbolithiation proceeded with modest to high diastereoselectivity to deliver cyclic or spirocyclic ring systems. The stereoselectivity of these intramolecular carbolithiations was examined using density function calculations to evaluate plausible transition state models.
Bahde
Robert J
RJ
Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, California 92697-2025, USA.
Rychnovsky
Scott D
SD
D000588:Amines / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D003500:Cyclization; D007202:Indicators and Reagents / Q000737:chemistry*; D008094:Lithium / Q000737:chemistry*; D010084:Oxidation-Reduction
D000588:Amines; D007202:Indicators and Reagents; D002244:Carbon; D008094:Lithium