Synthesis of 5-pyridyl-2-furaldehydes via palladium-catalyzed cross-coupling with triorganozincates.

ABSTRACT

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.