【摘要】 采用B3LYP／6-31G**方法在Gaussian03程序下,优化氢化卟吩的结构和能量,并寻找与内氢迁移反应相关的过渡态构型,通过比较,分析β位氢化对内氢迁移反应速率的影响。计算结果表明,β位氢化会迅速降低体系cis→trans的内氢迁移反应速率(达到10-4数量级),其影响明显高于β位取代。更多还原

【Abstract】 A theoretical study of the mechanism and kinetics of the inner hydrogen atom-transfer process inβ-dihydroporphine ( BH2 ) is presented. The structures and energies of reactants, products and transition-states in the transfer reaction of inner hydrogen atoms in BH, are calculated with B3LYP/6-31G* * method under certain symmetry restriction. The calculated results show that compared with porphine( PH2 ) ,β-hydrogenation can decrease speeds of cis→trans reactions by a foctor of 10 -4 , the effects ofβ-hydrogenation are obviously larger than those ofβ-substitution.更多还原