DISMAB, Sezione di Chimica Organica A. Marchesini, Università di Milano, via Venezian 21, 20133 Milano, Italy.
J Org Chem. 2010 Oct 15;75(20):6923-32. doi: 10.1021/jo101501u.
A variety of 3-vinyl-substituted imidazo[1,5-a]indole derivatives were synthesized by intramolecular Pd-catalyzed cyclization of the title allenamides through either a domino carbopalladation/exo-cyclization process or a novel hydroamination reaction that proceeds smoothly under microwave irradiation. Both the observed pathways involve a π-allyl-palladium(II) complex arising from insertion of the allene group into a palladium(II) species, the latter being formed in situ by the intervention of an aryl iodide or of the N-H group. In both cases, the role of nucleophile is covered by the indole nitrogen.
多种 3-乙烯基取代的咪唑并[1,5-a]吲哚衍生物通过标题烯酰胺的分子内 Pd 催化环化反应合成，该反应通过串联的碳钯化/外环化过程或在微波辐射下顺利进行的新型氨化反应来实现。观察到的两条途径都涉及到一个π-烯丙基-钯 (II) 配合物，该配合物是由烯丙基插入钯 (II) 物种中形成的，后者是由芳基碘化物或 N-H 基团的介入原位形成的。在这两种情况下，亲核试剂的作用都由吲哚氮来承担。
