%0 Journal Article
%T NHC Catalysis for Umpolung Pyridinium Alkylation via Deoxy-Breslow Intermediates.
%A Wu T
%A Tatton MR
%A Greaney MF
%J Angew Chem Int Ed Engl
%V 61
%N 15
%D 04 2022 4
%M 35103381
%F 16.823
%R 10.1002/anie.202117524
%X Umpolung N-heterocyclic carbene (NHC) catalysis of non-aldehyde substrates offers new pathways for C-C bond formation, but has proven challenging to develop in terms of viable substrate classes. Here, we demonstrate that pyridinium ions can undergo NHC addition and subsequent intramolecular C-C bond formation through a deoxy-Breslow intermediate. The alkylation demonstrates, for the first time, that deoxy-Breslow intermediates are viable for catalytic umpolung of areniums.