为了探索其光化学反应的区域选择性,已经合成了许多混合酸酐(RC(O)OC(O)R')。光化学反应产物、量子产率和反应速率已经确定。对于那些不含 α-氢的化合物,在辐照时可以获得高区域选择性,可以根据相对的 CO 键解离能来理解。反应可以通过分子内电子转移猝灭。对于含有α-氢原子的化合物,Norrish II型反应比相应的CO裂解反应快,导致区域选择性差
Mixed anhydrides: physical properties influenced by molecular structure
摘要:
A series of mixed anhydrides has been prepared and characterized. The reduction potentials and the electronic absorption spectra show an interesting systematic variation which is dependent on the steric requirements of the substituents. X-ray structural results are consistent with theoretical calculations that predict structural variations which are also dependent on the size of the substituent at the anhydride terminus. Taken together, these data show that the relative molecular orbital energies, as influenced by the relative dihedral angle of the two anhydride carbonyl groups, are responsible for the observed changes in physical properties.