Dihydropyridones: catalytic asymmetric synthesis, N- to C-sulfonyl transfer, and derivatizations.

EaStCHEM, School of Chemistry, University of St Andrews, North Haugh, St Andrews, Fife, UK.
Angewandte Chemie International Edition (Impact Factor: 13.73). 03/2012; 51(15):3653-7. DOI: 10.1002/anie.201109061
Source: PubMed

ABSTRACT Benzotetramisole (1) promotes the reaction of ammonium enolates derived from arylacetic acids with N-tosyl-α,β-unsaturated ketimines, thus giving dihydropyridones with high diastereo- and enantiocontrol. These products readily undergo N- to C-sulfonyl photoisomerization and are derivatized to afford stereodefined piperidines and tetrahydropyrans.

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