Stereocontrol in Preparation of Cyclopalladated Alkylaromatic Oximes and Evaluation of Their Stereoselective Esterase-Type Catalytic Activity
作者:Sergey Z. Vatsadze、Aleksei V. Medved’ko、Sergey A. Kurzeev、Oleg I. Pokrovskiy、Olga O. Parenago、Mikhail O. Kostenko、Ivan V. Ananyev、Konstantin A. Lyssenko、Dmitri A. Lemenovsky、Gregory M. Kazankov、Valery V. Lunin
DOI:10.1021/acs.organomet.7b00410
日期:2017.8.28
with fast subsequent cyclopalladation, so it was possible to perform ortho-palladation of E-oxime in kinetic resolution mode with removal of unreacted Z-oxime. Comparatively rare cis-structure of cyclopalladated oxime dimer was proved by means of single-crystal X-ray study. For the first time, it was shown that ortho-palladated chiral oximes behave as enantioselective catalyst in the hydrolysis of chiral
研究了2'-甲基丁二苯甲酮肟的立体化学,其E-和Z-异构体的原钯化速率以及各自的Pd配合物的催化活性。通过手性多糖柱上的超临界流体色谱法首次建立了肟的全部立体异构体组成。结果表明,(S)-2'-甲基丁苯酮肟(1 S)和(R)-2'-甲基丁苯酮肟(1 R)的E / Z-异构体的对映体过量均等于92±2。研究表明,虽然E-异构体非常快地被邻位钯化,其Z-配体不进入该反应。然而,与Pd(II)配位后,Z-肟缓慢异构化为E-型,随后快速发生环钯反应,因此可以动力学拆分方式进行E-肟的邻位钯反应,同时去除未反应的Z-肟。通过单晶X射线研究证明了环钯酸肟二聚体的相对稀少的顺式结构。对于第一次,它表明邻-palladated手性肟表现为手性酯的对映选择性水解催化剂。