Tandem Cyclizations Involving Carbene as an Intermediate: Photochemical Reactions of Substituted 1,2-Diketones Conjugated with Ene-Yne
作者:Kazuhiko Nakatani、Kaoru Adachi、Kazuhito Tanabe、Isao Saito
DOI:10.1021/ja990763q
日期:1999.9.1
studying tandem cyclizations involving carbene. The photocyclization of 1,2-diketones conjugated with ene-yne to (2-furyl)carbene was employed as a carbene-generating system. Upon photoirradiation of 1,2-diketones possessing biphenyl and 2-acetyl-1-cyclopentenyl systems as a carbene trapping unit in aprotic solvents, we observed tandem cyclizations via a carbene intermediate to produce fluorenylfuran
我们研究了一种新系统的光反应,其中卡宾发生器和卡宾陷阱包含在同一分子中,用于研究涉及卡宾的串联环化。将与烯-炔共轭的 1,2-二酮光环化为(2-呋喃基)卡宾作为卡宾生成系统。在对具有联苯和 2-乙酰基-1-环戊烯基系统作为卡宾捕获单元的 1,2-二酮在非质子溶剂中进行光照射后,我们观察到通过卡宾中间体串联环化,分别以几乎定量的产率生产芴基呋喃和联呋喃衍生物。串联环化的溶剂依赖性清楚地表明,在稳态光照射条件下,1,2-二酮与(2-呋喃基)卡宾平衡。