A new and efficient route to 7-ethyl-1H-furo[2,3-g]indazole (2) has been developed. Treatment of 4,5-dihydro-7-(1-hydroxyethyl)indazole (12) with hydrochloric acid in ethanol resulted in a concomitant dehydration and aromatization to afford the title compound in good yield.
Microwave-assisted synthesis of 4-keto-4,5,6,7-tetrahydrobenzofurans
The use of TMSCI in methanol under microwave irradiation allows the facile intramolecular condensation of a large panel of triketones, giving rise to 4-keto-4,5,6,7-tetrahydrobenzofurans in good to excellent yields. (C) 2008 Elsevier Ltd. All rights reserved.