B12 超支化聚合物的合成、表征及催化功能

Synthesis, characterization and catalytic function of a B12-hyperbranched polymer.

机构信息

Department of Chemistry and Biochemistry, Graduate School of Engineering, Kyushu University, Fukuoka, 819-0395, Japan.

出版信息

Dalton Trans. 2010 Mar 28;39(12):3035-42. doi: 10.1039/b923924c. Epub 2010 Jan 20.

PMID:20221537

Abstract

A new hybrid catalyst composed of a vitamin B(12) derivative and a hyperbranched polymer (HBP) was synthesized and characterized by UV-vis and ESR spectroscopy as well as AFM. The B(12)-HBP showed good properties as a homogenous catalyst. The covalently-immobilized B(12) moieties were efficiently solvated and the cobalt centers were accessible for pyridine guests. The B(12)-HBP showed high reactivity to 2-phenethylbromide and increased selectivity for reductive dimerization in the presence of TiO(2) with UV light irradiation.

摘要

一种新型的混合催化剂由维生素 B(12)衍生物和超支化聚合物（HBP）组成，通过紫外可见光谱、电子顺磁共振光谱和原子力显微镜进行了合成和表征。B(12)-HBP 表现出良好的均相催化剂性能。共价固定的 B(12)部分得到了有效溶剂化，钴中心对吡啶配体具有可及性。B(12)-HBP 在 TiO(2)存在下，在紫外光照射下对 2-苯乙基溴具有高反应性，并且对还原二聚体具有更高的选择性。