Diastereoselective synthesis of functionalised carbazoles via a sequential Diels-Alder/ene reaction strategy
Diastereoselective synthesis of functionalised carbazoles via a sequential Diels-Alder/ene reaction strategy
复制标题
通过连续 Diels-Alder/ene 反应策略非对映选择性合成官能化咔唑
DOI：
10.1039/c5ra00499c
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发表时间：
2015
期刊：
影响因子：
3.9
通讯作者：
Cowell J
中科院分区：
文献类型：
--
作者：
Cowell J
描述了一种操作简单的一锅，三组分，非对映选择性的饱和咔唑和相关的吡嗪[3,4-b]吲哚的合成，基于两个连续的分子间周环反应。反应序列涉及3-乙烯基- 1h -吲哚的分子间diols - alder （D-A）反应，含有一个吸电子的n保护基团，与合适的亲二酚。由于n保护基团的吸电子性质，生成的D-A环加合物被充分稳定，从而允许随后与添加的亲烯试剂进行原位非对映特异性分子间烯反应，生成具有相对立体控制多达四个立体中心的功能化咔唑。
An operationally simple one-pot, three-component, diastereoselective synthesis of saturated carbazoles and related pyridazino[3,4-b]indoles, based on two sequential intermolecular pericyclic reactions, is described. The reaction sequence involves an intermolecular Diels–Alder (D–A) reaction of a 3-vinyl-1H-indole, containing an electron withdrawing N-protecting group, with a suitable dienophile. Due to the electron withdrawing nature of the N-protecting group the resultant D–A cycloadducts are sufficiently stabilised to allow for a subsequent in situ diastereospecific intermolecular ene reaction to take place with an added enophile, generating functionalised carbazoles with relative stereocontrol of up to four stereocentres.