Regiocontrolled Cu<sup>I</sup>-Catalyzed Borylation of Propargylic-Functionalized Internal Alkynes
作者:Abraham L. Moure、Ramón Gómez Arrayás、Diego J. Cárdenas、Inés Alonso、Juan C. Carretero
DOI:10.1021/ja300627s
日期:2012.5.2
orbitalic influence from the propargylic group, matched with ligand and substrate size effects, as key factors involved in the high β-selectivity. The vinylboronates allowed the stereoselective synthesis of trisubstituted olefins, while allylic substitution of the SO(2)Py group without affecting the boronate group provided access to formal hydroboration products of unbiased dialkylalkynes.
在铜(I)催化的二烷基内炔与双(频哪醇)二硼的硼化中已经实现了良好的反应性和区域控制。炔丙基极性基团(OH、OR、SAr、SO(2)Ar 或 NHTs)的存在,与作为配体的 PCy(3) 结合,可以最大限度地提高反应性和位点选择性(β 对炔丙基功能)。DFT 计算表明来自炔丙基的微妙轨道影响与配体和底物尺寸效应相匹配,是高β-选择性的关键因素。乙烯基硼酸酯允许立体选择性合成三取代烯烃,而 SO(2)Py 基团的烯丙基取代而不影响硼酸酯基团提供了获得无偏二烷基炔烃的正式硼氢化产物的途径。