Microwave-assisted furan synthesis

A microwave-assisted synthesis of polysubstituted furans via the Paal-Knorr reaction was reported. Thus, furans were easily obtained in good yields by heating diketones under microwave irradiation in acid solution <05EJOC5277>. 

Minetto et al. (2004) carried out synthesis of tetrasubstituted pyrroles (and trisub-stituted furans) in a three-step reaction of P-ketoester with an aldehyde followed by oxidation to give number of substituted 1,4-dicarbonyl compounds, which is further cyclized by microwave-assisted with the Paal-Knorr reaction. 

Microwave-assisted synthesis of following difuran and furan-thiophene derivatives via Suzuki coupling was investigated by Lin and Lin (2005). 

The Paal-Knorr synthesis of furans as well as thiophenes and pyrroles has been carried out on solid support and a library of heterocyclic compounds has been prepared <2003SL711>. It has been shown that the acid-catalyzed synthesis of 2,3>4-substituted furans from 1,4-diketones can be assisted by microwave irradiation <20040L389>. 

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