Catalytic asymmetric synthesis of 1,1-disubstituted tetrahydro-β-carbolines by phase-transfer catalyzed alkylations

• DOI: 10.1039/c0cc04447d
• Publication Date: 2010-11-19T16:00:23Z
• Authors: Seiji Shirakawa; Kun Liu; Hironobu Ito; Keiji Maruoka
• Keywords: Alkylation; Molecular Structure; Stereoisomerism; 01 natural sciences; Catalysis; Carbolines; 0104 chemical sciences

Efficient catalytic asymmetric synthesis of 1,1-disubstituted tetrahydro-β-carbolines has been achieved via asymmetric alkylation of 1-cyanotetrahydro-β-carbolines using a binaphthyl-modified N-spiro-type chiral phase-transfer catalyst. This is a valuable example of hitherto difficult highly enantioselective alkylations at α-carbon of the cyano group under phase-transfer conditions.