Synthesis 2016; 48(14): 2271-2279
DOI: 10.1055/s-0035-1561634
paper
© Georg Thieme Verlag Stuttgart · New York

Synthesis of Chiral Tetrahydroisoquinoline and C 2-Symmetric Bistetrahydroisoquinoline Ligands and Their Application in the Enantioselective Henry Reaction

Duc Thinh Khong
School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, N1.2–B1-14, Singapore 637459   Email: zaher@ntu.edu.sg
,
Zaher M. A. Judeh*
School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, N1.2–B1-14, Singapore 637459   Email: zaher@ntu.edu.sg
› Author Affiliations
Further Information

Publication History

Received: 16 November 2015

Accepted after revision: 08 April 2016

Publication Date:
01 June 2016 (online)


Abstract

Application of chiral tetrahydroisoquinoline and bistetrahydroisoquinoline scaffolds in asymmetric reactions is limited by the inefficient synthesis of their chiral structural variants. We have conveniently synthesized 24 such variants and applied them as ligands in the enantioselective Henry reaction. The conformational rigidity of these ligands and the size of the coordination sphere control the enantioselectivity of the products. The conformationally rigid chiral tetrahydroisoquinoline THIQ–Cu(OAc)2·H2O complex successfully catalyzed the enantioselective Henry reaction between various aldehydes and nitromethane and gives the β-nitro alcohol adducts in up to 96% yield and 80% ee.

Supporting Information