Brønsted-acid catalyzed condensation-Michael reaction-Pictet–Spengler cyclization—highly stereoselective synthesis of indoloquinolizidines

Abstract

A highly diastereoselective methodology for the efficient synthesis of functionalized indolo[2,3-a]quinolizidine skeletons in a one-pot operation has been developed. The protocol makes use of simple and inexpensive starting materials such as tryptamines, 1,3-dicarbonyl compounds and α,β-unsaturated aldehydes in the presence of a Brønsted acid catalyst.