ИСТИНА

The dihydrogen-bonded (DHB) complexes are known to form at the first step of proton-transfer reaction. These complexes previously investigated for different types of metal hydrides and hydrides of main group elements, but for metal tetrahydroborates study of influence intermolecular interactions on chemical properties of such compounds. The mechanism of acid mediated transformation of transition metal tetrahydroborates was thoroughly studied by means of combination of experimental (IR and NMR, 190-300 K) and computational (DFT/M06) methods. Formation of DHB complexes as the first reaction step and their thermodynamic characteristic was established experimentally. By means of theoretical investigation possible coordination modes of DHB complexes were revealed. Despite of existence a large number of DHB different types (mono-, bi- and trifurcate complexes) and competition between these forms, only one type of DHB bifurkate complex with participation of terminal and bridge hydrides of tetrahydroborate-group is active intermediate of the reactions.