Aldehyde umpolung by N-heterocyclic carbenes: NMR characterization of the Breslow intermediate in its keto form, and a spiro-dioxolane as the resting state of the catalytic system.
Berkessel
Albrecht
A
Cologne University, Department of Chemistry, Greinstrasse 4, 50939 Köln, Germany. berkessel@uni-koeln.de
Elfert
Silvia
S
Etzenbach-Effers
Kerstin
K
Teles
J Henrique
JH