ChemInform Abstract: Organoselenium and DMAP Co-Catalysis: Regioselective Synthesis of Medium-Sized Halolactones and Bromooxepanes from Unactivated Alkenes

A catalytic system consisting of bis(4-methoxyphenyl)selenide and 4-(dimethylamino)pyridine (DMAP) has been developed for the regioselective synthesis of medium-sized bromo/iodo lactones and bromooxepanes possessing high transannular strain. (77)Se NMR, mass spectrometry and theoretical studies reveal that the reaction proceeds via a quaternary selenium intermediate.