Attempted Simmons-Smith reaction on α-oxoketene dithioacetals: A new general route to 3,4-substituted and annelated thiophenes
作者:Laxminarayan Bhat、Abraham Thomas、Hiriyakkanavar Ila、Hiriyakkanavar Junjappa
DOI:10.1016/s0040-4020(01)88342-3
日期:1992.11
A new general synthesis of 3- and 3,4-substituted 4a–q, 3,4-annelated 7a–d and condensed tricyclic 9a–e thiophenes has been developed through Simmons-Smith reaction on the respective α-oxoketene dithioacetals. Extension of the reaction to α-cinnamoylketene dithioacetals 10a–e and its higher enyl analogs 13a–d, 15a–c gave the corresponding 3-styryl 11a–e and 3-di- and trienyl 14a–d, 16a–c thiophenes
通过Simmons-Smith反应在相应的α-氧杂环丁烯二硫缩醛上开发了3和3,4-取代的4a-q,3,4-退火的7a-d和稠合的三环9a-e噻吩的新的一般合成物。将反应扩展至α-肉桂酰基烯酮二硫缩醛10a-e及其高级烯基类似物13a-d,15a-c,可得到相应的3-苯乙烯基11a-e和3-二-和三烯基14a-d,16a-c噻吩区域选择性方式。已经提出了一种可能的机制,该机制涉及通过二价硫上的类胡萝卜素亚甲基插入而形成的基分子的不寻常的分子内羟醛缩合。