Carbon−Carbon Bond Formation and Pyrrole Synthesis via the [3,3] Sigmatropic Rearrangement of <i>O</i>-Vinyl Oxime Ethers
作者:Heng-Yen Wang、Daniel S. Mueller、Rachna M. Sachwani、Hannah N. Londino、Laura L. Anderson
DOI:10.1021/ol100659q
日期:2010.5.21
A new method for the synthesis of 2,4- and 2,3,4-substituted pyrroles in two or three steps from commercially available ketones and allyl hydroxylamine is described. An iridium-catalyzed isomerization reaction has been developed to convert O-allyl oximes to O-vinyl oximes, which undergo a facile [3,3] rearrangement to form 1,4-imino aldehyde Paal−Knorr intermediates that cyclize to afford the corresponding
描述了一种新的方法,该方法由市售的酮和烯丙基羟胺分两步或三步合成2,4-和2,3,4-取代的吡咯。已开发出铱催化的异构化反应,可将O-烯丙基肟转化为O-乙烯基肟,然后将其进行简便的[3,3]重排以形成1,4-亚氨基醛Paal-Knorr中间体,然后环化生成相应的吡咯。讨论了异构化和吡咯形成的优化方法和实例。