THE ROLE OF CHARGE-TRANSFER PROCESSES IN PHOTOCHEMICAL-REACTIONS

The probabilities of the occurrence of photochemical processes in some 3-substituted derivatives of coumarin I and coumarin IH as well as in 4-trifluoromethylcoumarin I were studied by quantum-chemical methods. The probabilities for different pathways of die photoreactions of alkylaminocoumarins appear to be a function of the type and position of a substituent and of the nature of orbitals in the electronically excited state, as found from the values of relevant bond energies calculated in the electrostatic approximation.