Silver-catalysed asymmetric [3+2] cycloaddition for the construction of 5–5-membered 1,3′-indolyl pyrrole atropisomers

Abstract

An atropoenantioselective Ag-catalysed [3+2] cycloaddition of N-alkynyl ketones with isocyanides has been developed to access 5–5-membered 1,3′-indolyl pyrroles bearing C–N axial chirality in high yields and excellent enantioselectivities. The resulting products exhibit excellent thermal stability and, upon derivatisation to monophosphine compounds, serve as effective chiral ligands in Pd-catalysed asymmetric reactions.