Inversion of Configuration at the Metal in Diastereomeric Imido Alkylidene Monoaryloxide Monopyrrolide Complexes of Molybdenum

被引：44

作者：

Marinescu, Smaranda C. ^{[1
]}

Schrock, Richard R. ^{[1
]}

Li, Bo ^{[2
]}

Hoveyda, Amir H. ^{[2
]}

机构：

[1] MIT, Dept Chem 6 331, Cambridge, MA 02139 USA

[2] Boston Coll, Dept Chem, Merkert Chem Ctr, Chestnut Hill, MA 02467 USA

来源：

JOURNAL OF THE AMERICAN CHEMICAL SOCIETY | 2009年 / 131卷 / 01期

基金：

美国国家卫生研究院; 美国国家科学基金会;

关键词：

TOPOLOGICAL REPRESENTATION; METATHESIS; STEREOISOMERISM; PSEUDOROTATION; CATALYSTS;

D O I：

10.1021/ja808308e

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

The two diastereomers of Mo(NAr)(CHCMe2Ph)(2,5-dimethylpyrrolide)(1), (SMR1)-2 and (RMR1)-2, respectively, where 1 is an enantiomericatly pure (R) phenoxide and Ar = 2,6-diisopropylphenyl, form adducts with PMe3. One of these ((RMR1)-2(PMe3)) has been isolated. An X-ray structure reveals that PMe3 has added trans to the pyrrolide; it is a model for where an olefin would attack the metal. Trimethylphosphine will catalyze slow interconversion of (SMR1)-2 and (RMR1)-2 via formation of weak PMe3 adducts. Reactions between (SMR1)-2 or (RMR1)-2 and ethylene yield Mo(NAr)(CH2)(Me(2)Pyr)(1) species in which the configuration at Mo is inverted by ethylene at a rate of the order of the NMR time scale at 22 degrees C via formation of metallacyclobutane intermediates with imido and aryloxide ligands in axial positions. A reactant olefin is proposed to approach Mo and the product otefin to leave Mo trans to the pyrrolide.

引用

页码：58 / +

页数：4

共 26 条

[1] Initiators of the type Mo(NAr)(CHR′)(OR")2 for the controlled polymerization of diethyldipropargylmalonate [J].