Toward 2-Thiophyne: Ketocarbene versus Hetaryne Intermediates from 2-(Trimethylsilyl)thiophen-3-yl Triflate
作者:Iago Pozo、Agustín Cobas、Diego Peña、Enrique Guitián、Dolores Pérez
DOI:10.1021/acs.orglett.1c02552
日期:2021.10.1
The reaction of 2-(trimethylsilyl)thiophen-3-yl triflate with CsF in the presence of 2,3,4,5-tetraphenylcyclopentadienone affords 4,5,6,7-tetraphenylbenzo[b]thiophene, as it would be expected from the hypothesized generation and trapping of 2-thiophyne. However, a detailed experimental and computational study discards the intermediacy of this elusive 5-membered hetaryne. Instead, a complex mechanism
在 2,3,4,5-四苯基环戊二烯酮存在下,2-(三甲基甲硅烷基)噻吩-3-基三氟甲磺酸酯与 CsF 反应得到 4,5,6,7-四苯基苯并[ b ]噻吩,正如预期的那样2-噻吩的假设生成和捕获。然而,详细的实验和计算研究抛弃了这种难以捉摸的 5 元杂炔的中间体。相反,提出了一种复杂的机制,包括生成中间体酮卡宾,该中间体与环戊二烯酮相加得到可分离的三环中间体,然后进行热重排。