这项工作描述了新型催化剂5-(3-溴,4-氨基)苯基-10,15,20-三苯基-2,3,7,8,12,13,17,18-八溴卟啉锰的合成与表征。 III)氯化物(Mn III Br 9 APTPPCl)。该化合物,Mn III APTPPCl和Mn III TPPCl被用作环己烷氧化的催化剂,使用PhIO或PhI(OAc)2作为氧化剂。与其他催化剂相比,在与PhIO和PhI(OAc)2的反应中,Mn III Br 9 APTPPCl导致更高的产物收率。此外,首次观察到在使用PhI(OAc)2的反应中第三代(β-八溴代)催化剂的回收率作为氧化剂。加入咪唑或水作为添加剂进行反应。与咪唑的反应在所有研究的系统中均显示出较高的环己醇收率。对于使用PhIO的系统,还观察到催化剂氧化破坏的减少。所有使用PhIO和水的系统导致产品产量的增加。但是,几乎所有这些系统的催化剂回收率都很低。然而,这是首次证明
Synthesis and catalytic properties of manganese complexes of substituted tetraphenylporphyrins in the stereoselective hydroxylation of cholesterol
摘要:
Manganese(III) complexes of 5-(p-aminophenyl)-10,15,20-triphenylporphyrin, 2-(2-carboxyvinyl)-5,10,15,20-tetraphenylporphyrin, and their derivatives containing electron-donor and electron-acceptor substituents have been synthesized. Manganese(III) porphyrinates (PMn) are catalytically active in the stereoselective hydroxylation of cholesterol to form 3 beta,5 alpha-cholestanediol. The influence of substitutents in the porphyrin ring on the ability of PMn to associate in solution, the hydroxylation rate constants, and the turnover number of the catalyst are discussed.