Microwave-assisted Paal-Knorr reaction. A rapid approach to substituted pyrroles and furans.
[reaction: see text] An array of tetrasubstituted pyrroles (and trisubstituted furans) was obtained using a simple three-step procedure. Functional homologation of a beta-ketoester with an aldehyde followed by oxidation gave a series of differently substituted 1,4-dicarbonyl compounds that can be rapidly cyclized with the Paal-Knorr procedure carried out under microwave irradiation.
Minetto
Giacomo
G
Dipartimento Farmaco Chimico Tecnologico, Università degli Studi di Siena, Via A. Moro, 53100 Siena, Italy.
Raveglia
Luca F
LF
Taddei
Maurizio
M