Virtually Complete Control of Simple and Face Diastereoselectivity in the Michael Addition Reactions between Achiral Equivalents of a Nucleophilic Glycine and (<i>S</i>)- or (<i>R</i>)-3-(<i>E</i>-Enoyl)-4-phenyl-1,3-oxazolidin-2-ones: Practical Method for Preparation of β-Substituted Pyroglutamic Acids and Prolines
作者:Vadim A. Soloshonok、Hisanori Ueki、Rohit Tiwari、Chaozhong Cai、Victor J. Hruby
DOI:10.1021/jo0495438
日期:2004.7.1
stereochemical outcome of the Michael addition reactions between nucleophilic glycine equivalents and α,β-unsaturated carboxylic acid derivatives: The addition reactions between achiral Ni(II)-complex of the Schiff base of glycine with o-[N-α-pycolylamino]acetophenone and (S)- or (R)-3-(E-enoyl)-4-phenyl-1,3-oxazolidin-2-ones were shown to occur at room temperature in the presence of nonchelating organic
这项研究表明,用于控制亲核甘氨酸等价物和α,β -不饱和羧酸衍生物之间的迈克尔加成反应的立体化学结果的新策略:非手性的Ni之间的加成反应(II)甘氨酸的席夫碱用的复形ö - [ N -α-羟甲基氨基]苯乙酮和(S)-或(R)-3-(E(-烯酰基)-4-苯基-1,3-恶唑烷-2-酮在室温下在非螯合有机碱存在下发生,最显着的是,在两个新形成的立体异构中心均具有很高的立体选择性。因此,发现手性的4-苯基-1,3-恶唑烷-2-酮部分可有效地控制甘氨酸衍生的烯酸酯的非对映选择性和迈克尔受体的C,C双键。在这项工作中开发的新策略在方法论上优于以前的方法,最显着的是在通用性和综合效率方面。优异的化学收率和非对映选择性,再加上简单的实验步骤,使得本发明的方法可立即用于制备各种3取代的焦谷氨酸和相关氨基酸(谷氨酸,谷氨酰胺,脯氨酸等)。