Dynamic behaviour attributed to chiral carbohydrate substituents of N-heterocyclic carbene ligands in square planar nickel complexes.
Dynamic behaviour attributed to chiral carbohydrate substituents of N-heterocyclic carbene ligands in square planar nickel complexes.
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DOI：
10.1039/c0dt01833c
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发表时间：
2011-06
影响因子：
4
通讯作者：
Teppei Shibata;S. Ito;M. Doe;R. Tanaka;H. Hashimoto;I. Kinoshita;S. Yano;T. Nishioka
中科院分区：
文献类型：
--
作者：
Teppei Shibata;S. Ito;M. Doe;R. Tanaka;H. Hashimoto;I. Kinoshita;S. Yano;T. Nishioka
以甲基或苄基为n取代基的乙酰化葡萄糖氨基结合n -杂环碳（NHC）配体的镍配合物在溶液中表现出两种动态行为(1)H核磁共振光谱。其中一种动力学行为归因于反旋体和顺旋体，它们是由不对称的NHC配体围绕Ni-C键的轴旋转而产生的。另一个原因是同旋体的非对映体，这是由于咪唑烷基环和NHC配体中的手性碳水化合物基团的相反旋转而产生的。对以乙酰化氨基葡萄糖和苄基为n取代基的NHC配体的镍配合物的晶体分析表明，在固体状态下，每个NHC配体的氨基葡萄糖与另一个NHC配体的苯环之间存在CH-π相互作用。
Nickel complexes having acetylated glucopyranosyl group incorporated N-heterocyclic carbene (NHC) ligands with methyl or benzyl groups as an N-substituent exhibit two kinds of dynamic behaviours in solution (1)H NMR spectroscopy. One of the dynamic behaviours is attributed to the anti- and syn-rotamers, which occur by the rotation of the unsymmetrical NHC ligands around the axes of the Ni-C bonds. The other is attributed to the diastereomers of the syn-rotamers, which occur by opposite rotation of the imidazolylidene rings and the chiral carbohydrate group incorporated into the NHC ligands. Crystallographic analysis of the nickel complex having the NHC ligand with acetylated glucopyranosyl and benzyl groups as N-substituents showed CH-π interaction between the glucopyranosyl unit of each NHC ligand and the phenyl ring of the other NHC ligand in the complex in the solid state.