Divergent Synthetic Strategy Leading to Structurally Diverse Pyrrolidines and Piperidines from Common γ-Aminoalkyl Butenolide and Aldehyde Precursors
作者:José M. Aurrecoechea、Rubén Suero、Esther de Torres
DOI:10.1021/jo0614487
日期:2006.11.1
Condensation between aldehydes and the secondary amino function of 5-(aminoalkyl)furan-2(5H)-ones, obtained by the silyloxyfuran dienolate addition to imine-type derivatives, produces either aminoalkylbenzotriazoles or 1,2,3,4-tetrahydropyridines. The former can be reduced with SmI2 to generate α-aminoalkyl radicals that are trapped by the α,β-unsaturated lactone moiety yielding substituted pyrrolidines
通过将甲硅烷氧基呋喃二烯酸酯加成亚胺型衍生物而获得的醛与5-(氨基烷基)呋喃-2(5H)-一的仲氨基官能团之间的缩合产生氨基烷基苯并三唑或1,2,3,4-四氢吡啶。前者可用SmI 2还原以生成被α,β-不饱和内酯部分捕获的α-氨基烷基自由基,非对映选择性地产生取代的吡咯烷,而后者的催化加氢则提供了哌啶类似物的异构体。或者,SmI 2在酸的存在下促进四氢吡啶的还原也导致中间α-氨基烷基自由基参与分子间或分子内烯烃加成反应。以各种方式进一步控制内酯官能度可得到基于吡咯烷或哌啶结构基序的许多有趣的衍生物。结果,从一组常见的简单材料开始,只需几个步骤即可获得高度的结构多样性。