Multiple Hydrogen-Bond Activation in Asymmetric Brønsted Acid Catalysis

Hsuan-Hung Liao; Chien-Chi Hsiao; Iuliana Atodiresei; Magnus Rueping

doi:10.1002/chem.201800677

Multiple Hydrogen-Bond Activation in Asymmetric Brønsted Acid Catalysis

Chemistry. 2018 May 28;24(30):7718-7723. doi: 10.1002/chem.201800677. Epub 2018 May 3.

Authors

Hsuan-Hung Liao¹, Chien-Chi Hsiao¹, Iuliana Atodiresei¹, Magnus Rueping^{1

2}

Affiliations

¹ Institute of Organic Chemistry, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany.
² King Abdullah University of Science and Technology (KAUST), KAUST Catalysis Center (KCC), Thuwal, 23955-69 00, Saudi Arabia.

PMID: 29722908
DOI: 10.1002/chem.201800677

Abstract

An efficient protocol for the asymmetric synthesis of chiral tetrahydroquinolines bearing multiple stereogenic centers by means of asymmetric Brønsted acid catalysis was developed. A chiral 1,1'-spirobiindane-7,7'-diol (SPINOL)-based N-triflylphosphoramide (NTPA) proved to be an effective Brønsted acid catalyst for the in situ generation of aza-ortho-quinone methides (aza-o-QMs) and their subsequent cycloaddition reaction with unactivated alkenes to provide the products with excellent diastereo- and enantioselectivities. In addition, DFT calculations provided insight into the activation mode and nature of the interactions between the N-triflylphosphoramide catalyst and the generated aza-o-QMs.

Keywords: Brønsted acids; cycloaddition; nitrogen heterocycles; organocatalysis; reactive intermediates.