Synthesis of 5-pyridyl-2-furaldehydes via palladium-catalyzed cross-coupling with triorganozincates.
5-Pyridyl- and 5-aryl-2-furaldehydes are prepared from furaldehyde diethyl acetal in a four-step, one-pot procedure:(i) deprotonation; (2) Li to Zn transmetalation; (3) Pd-mediated cross-coupling; (4) aldehyde deprotection. Triorganozincate 7 was found to transfer all three groups in the Pd-catalyzed cross-coupling reaction with haloaromatics.
Gauthier
Donald R
DR
Department of Process Research, Merck & Co., Inc., P.O. Box 2000, Rahway, NJ 07065, USA. donald_gauthier@merck.com
Szumigala
Ronald H
RH
Dormer
Peter G
PG
Armstrong
Joseph D
JD
Volante
R P
RP
Reider
Paul J
PJ