Donor–acceptor adducts of the mixed boron trihalides: adducts of dimethyl ether

Abstract

N.m.r. studies of halogen redistribution in dimethyl ether–boron trihalide adducts in solution show that equilibrium between mixed and unmixed-halogen adducts is attained rapidly. Near-statistical amounts of the mixed and unmixed-halogen species are present at equilibrium in the Me₂O,BF_nCl_{3 –n}(n= 0–3) system. Decomposition is a serious competing reaction in adducts containing boron-bromine and especially boron-iodine bonds. Exchange reactions and trends in the n.m.r. parameters are discussed.