Abstract Ten new oxo-stabilised phosphonium ylides containing substituted thiophene groups, as well as two deuterium-labelled analogues, are prepared and fully characterised. Upon flash vacuum pyrolysis at 800 °C, the simpler examples undergo extrusion of Ph3PO coupled with domino cyclisation to give thieno[3,2-b]furan and thieno[3,4-b]furan products but the corresponding approach to a thieno[2,3-b]furan fails. One ylide designed to give a thieno[3,4-b]furan instead gives phenylbutadiyne and 2-phenyl-3-vinylthiophene at 725 °C and the mechanism of this unusual process is elucidated by deuterium labelling. Attempts to access more complex heterocyclic products from extended methoxythienyl ylides failed. Two ylides bearing a 3-methyl-2-thienylacryloyl group gave 5-benzylbenzothiophene, 5-(α-methylbenzyl)benzothiophene and fluoreno[3,4-b]thiophene upon FVP at 800 °C and the mechanism was again elucidated by deuterium labelling.

中文翻译：

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含甲氧基噻吩和甲基噻吩基团的氧稳定鏻叶立德的快速真空热解

摘要 制备并充分表征了 10 种新的含取代噻吩基团的氧稳定鏻叶立德，以及两种氘标记的类似物。在 800 °C 下快速真空热解时，较简单的例子经历了 Ph3PO 的挤出和多米诺环化作用，得到噻吩并 [3,2-b] 呋喃和噻吩并 [3,4-b] 呋喃产品，但相应的方法是生成噻吩并 [3,2-b] 2,3-b]呋喃失效。一种设计用于产生噻吩并 [3,4-b] 呋喃的叶立德在 725 °C 下产生苯基丁二炔和 2-苯基-3-乙烯基噻吩，并通过氘标记阐明了这一不寻常过程的机制。试图从扩展的甲氧基噻吩基叶立德获得更复杂的杂环产物的尝试失败了。带有 3-甲基-2-噻吩基丙烯酰基的两个叶立德得到 5-苄基苯并噻吩、5-(α-甲基苄基)苯并噻吩和芴[3,