ABSTRACT
Owing to the large energetic driving force provided by the high energies of electronic excited states, single electron transfer (SET) is the key mechanistic event in a wide variety of photochemical processes. Photoinduced SET between neutral donors and acceptors results in generation of radical ions, highly reactive intermediates which participate in facile and selective reactions as part of mechanistic routes leading to product formation. SET oxidation of α-silylamines is thermodynamically more favorable than that of its nonsilicon containing counterparts owing to the thermodynamic stability of the resulting α-silylaminium radicals. SET photochemical investigations have focused on a wide variety of electron acceptors which are used either as SET-photosensitizers or reactants. SET-promoted photocyclization reactions of linked phthalimide acceptors and α-silyl-substituted polyheteroatom containing donors can be incorporated into novel strategies for the preparation of interesting cyclic substances. The unique features of SET-promoted photocyclization reactions of polydonor-linked phthalimides make radical fragmentation processes compatible with strategies for the efficient construction of highly functionalized macrocyclic targets.
