ABSTRACT The Mg─Mg‐bonded compound K(THF) 3 2 LMg─MgL 2 ( 1 , L = (2,6‐ i Pr 2 C 6 H 3 )NC(CH 3 ) 2 2− ) can promote reductive 4,4′‐homocoupling of pyridine and derivatives under ambient conditions, yielding the 4,4′‐dihydro‐4,4′‐bipyridinate products 2 – 6 . Interestingly, these species can be viewed as “dimerized” metal‐1,4‐dihydropyridinates (bis‐M‐DHPs) and can transfer hydrogen or deuterium (as proton and hydride) to pyridines, imines and alkenes. This may provide a facile access to new H/D‐donors, readily obtained from commercially available pyridines and a conveniently synthesized magnesium(I) complex, for controllable H‐transfer (HT) to different types of unsaturated molecules. The coupling and HT mechanisms were elucidated by DFT calculations.
Sun et al. (Thu,) studied this question.