DOI: 10.1016/j.cplett.2024.141782  (OpenAccess)

Unexpected Enhanced acidity of Diborane-Nitrogen Base complexes

The effect that borane and diborane have on the structure and acidity of various N-bases was analyzed using G4 ab-initio calculations. Although diborane is expected to be a stronger Lewis acid than borane, its interaction with N-bases is weaker due to the loss of one of its (3c,2e) bonds. Surprisingly, however, diborane has a significantly greater effect on the intrinsic acidity of these bases than borane. Upon deprotonation of the base, the interaction strength increases by a factor of 10 with diborane and only 3 with borane, as both the B–N and BH3···BH3 interactions are reinforced in diborane.