Enantiodivergent Synthesis of Tertiary α-Aryl 1-Indanones: Evidence Toward Disparate Mechanisms in the Palladium-Catalyzed Decarboxylative Asymmetric Protonation
作者:Cian Kingston、Patrick J. Guiry
DOI:10.1021/acs.joc.7b00303
日期:2017.4.7
Herein, we describe a study into the scope and origin of an enantiodivergent effect in the palladium-catalyzed decarboxylative asymmetric protonation. By switching the achiral proton source, both enantiomers of a series of tertiary α-aryl-1-indanones are readily accessed from the corresponding α-aryl-β-keto allyl esters. In this example of dual stereocontrol, enantioselectivities up to 94% (S) and
在这里,我们描述了对钯催化的脱羧不对称质子化中对映发散作用的范围和起源的研究。通过切换非手性质子源,可以容易地从相应的α-芳基-β-酮烯丙基酯获得一系列叔α-芳基-1-茚满酮的两个对映体。在双重立体控制的这个例子中,分别使用Meldrum的酸和甲酸可实现高达94%(S)和92%(R)的对映选择性。为了合理化这种绝对构型的开关,对脱羧不对称质子化的模棱两可机理进行了研究。提出了与甲酸反应的新型催化循环,并进行了各种实验研究。