Cascading Radical Cyclization of Bis-Vinyl Ethers: Mechanistic Investigation Reveals a 5-<i>exo</i>/3-<i>exo</i>/retro-3-<i>exo</i>/5-<i>exo</i> Pathway
作者:Natasha F. O’Rourke、Katherine A. Davies、Jeremy E. Wulff
DOI:10.1021/jo301565u
日期:2012.10.5
an iterative synthesis of oligo-vinyl ethers, followed by a radical cascade to provide a family of hexahydro-2H-furo[3,4-b]pyrans. Our results for the radical cascade were consistent with either a direct 6-endo-trig addition of a vinyl radical onto the first vinyl ether function or an initial 5-exo-trig addition, followed by rearrangement to the more stable anomeric radical intermediate. In this report
我们最近描述了低聚-乙烯基醚的迭代合成,然后进行自由基级联反应以提供六氢-2 H-呋喃[3,4- b ]吡喃家族。我们对自由基级联结果与任一个直接6-一致内切- trig的另外的乙烯基自由基在第一乙烯基醚功能或初始-5-外- trig的加成,随后重排为更稳定的端基异构体的自由基中间体。在此报告中,我们描述了旨在区分这两种可能性的进一步的机理研究,并得出结论,认为5- exo / 3- exo / retro-3- exo途径占主导地位。