Catalytic Amidomethylative [2+2+2] Cycloaddition of Formaldimine and Styrenes toward N-Heterocycles
Catalytic Amidomethylative [2+2+2] Cycloaddition of Formaldimine and Styrenes toward N-Heterocycles
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DOI：
10.1055/a-1710-7256
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发表时间：
2022-01-27
影响因子：
2.6
通讯作者：
Cui，Xin
中科院分区：
文献类型：
--
作者：
Lakmal，Hetti Handi Chaminda;Istre，Jacob;Cui，Xin
报道了烯烃与福尔马亚胺的化学转换催化[2+2+2]环加成反应。双(甲苯磺酰氨基)甲烷 (BTM) 和 1,2-二甲苯磺酰-1,2-二氮杂环丁烷 (DTD) 是高反应性甲苯磺酰甲醛亚胺的两种实验室稳定前体，已被证明是有效的。 BTM 作为福尔马亚胺的选择性释放剂，通过可能的“亚胺-烯烃-亚胺”加成，催化 [2+2+2] 反应生成六氢嘧啶产物。使用了 DTD 的独特催化逆 [2+2] 反应，并实现了所提出的具有高化学选择性的“亚胺-烯烃-烯烃”途径，用于合成 2,4-二芳基哌啶衍生物。这两种替代过程分别由简单且环境友好的催化剂 InCl3 和 FeBr2 催化。
Chemo-switchable catalytic [2+2+2] cycloaddition of alkenes with formaldimines is reported. Bis(tosylamido)methane (BTM) and 1,2-ditosyl-1,2-diazetidine (DTD), two bench-stable precursors for highly reactive tosylformaldimine, have been identified to be effective. BTM worked as a selective releaser of the formaldimine for catalytic [2+2+2] reactions toward hexahydropyrimidine products via a presumable ‘imine–alkene–imine’ addition. A unique catalytic retro-[2+2] reaction of DTD was used and has enabled a proposed ‘imine–alkene–alkene’ pathway with high chemoselectivity for the synthesis of 2,4-diarylpiperidine derivatives. The two alternative processes are catalyzed by the simple and environmentally benign catalysts InCl3and FeBr2, respectively.