University of Texas at Austin, Department of Chemistry , Austin, Texas 78712, United States.
Org Lett. 2017 Sep 15;19(18):4876-4879. doi: 10.1021/acs.orglett.7b02336. Epub 2017 Aug 29.
A single ruthenium complex catalyzes two discrete transformations resulting in the net conversion of an acetylenic pyrrole and alcohols to products of carbonyl anti-(α-amino)allylation. An initial catalytic process enables isomerization of an alkyne to a kinetically more reactive allene. A second catalytic process promotes alcohol-to-allene hydrogen transfer to form an aldehyde-allylruthenium pair that engages in regio- and diastereoselective carbonyl addition. A related reductive coupling of aldehydes mediated by 2-propanol also is described. The present catalytic processes represent rare examples of the use of alkynes as nucleophilic allylmetal precursors.
一种钌配合物可催化两种不同的转化反应，将炔基吡咯和醇转化为羰基反式-（α-氨基）烯丙基化产物。初始催化过程使炔烃异构化为动力学上更活泼的丙二烯。第二个催化过程促进醇向丙二烯的氢转移，形成醛-烯丙基钌对，从而进行区域和立体选择性的羰基加成。还描述了由 2-丙醇介导的相关醛的还原偶联。目前的催化过程代表了炔烃作为亲核烯丙基金属前体的罕见实例。
