Base-controlled selective construction of polysubstituted dihydrofuran and furan derivatives through an I2-mediated cyclization
摘要:
A base-controlled formal [3 + 2] cycloaddition of 1,3-dicarbonyl compounds to enones via an I-2-mediated cyclization was reported. Highly functionalized dihydrofurans and furans were selectively obtained under I-2/DMAP and I-2/DBU conditions in the cyclization step, respectively. (C) 2016 Elsevier Ltd. All rights reserved.
A simple and atom-economic synthesis of highly substituted thiophenes is demonstrated. Heating a solution of a chalcone and a linear/cyclic 1,3-dicarbonyl compound with elemental sulfur in CH3CN in the presence of NEt3 at 80 °C afforded the corresponding substituted thiophenes in good to excellent yields.