Efficient Synthesis of Five- and Seven-Membered-Ring Heterocycles by Rhodium(II)-Catalyzed [3+2] and [3+4] Cycloaddition of Diazodicarbonyl Compounds with Conjugated Dienes
Cycloaddition Reactions of Iodonium Ylides of Cyclic <i>β</i>-Diketones with 1,3-Dienes: Evidence for a Stepwise Mechanism
作者:Ioannis Alexiou、Efstathios P. Gogonas、Lazaros P. Hadjiarapoglou
DOI:10.1055/s-1999-2970
日期:1999.12
The irradiation of a cyclic β-dicarbonyl iodonium ylide with 1,3-diene in acetonitrile gives substituted dihydrofurans in moderate to high yields, presumably via a stepwise mechanism.
Electrochemical oxidation of 1,3-diketones in the presence of olefins afforded the formal [3+2] cycloaddition products, dihydrofuran derivatives or tetrahydrofuran derivatives. A mechanism involving attack of a radical intermediate to an olefin has been proposed.