Previously, we and others have reported zinc-catalyzed C-H borylations using H-BPin, H-BCat, (Cat = o-C6H4O2 ) and H-BDan. The coordination of these boranes through O/N to zinc electrophiles was proposed to be key for borylation. This is consistent with catalytic borylation not proceeding in a number of these systems when using (H-BBN)2 (which does not contain a Lewis basic O or N unit). More recently, we have used NacNacM-Y (M = Zn, Y = H or M = Al-Me, Y=Me) and sub-stoichiometric ammonium salts to form compound A that effects the C-H zincation and C-H alumination of arenes (Fig. , NacNac = {(2,6i Pr2C6H3)N(CH3)C}2CH). Given that NacNacM-R complexes can undergo -bond metathesis with hydroboranes to form organoboranes and NacNacM-H, we hypothesized that performing arene C-H zincation/alumination in the presence of (H-BBN)2 could enable catalytic C-H borylation to form Ar-BBN compounds. This would require the product from C-H metalation, NacNacM-Ar, to undergo -bond metathesis with (H-BBN)2 to produce Aryl-BBN and NacNacM-H. NacNacM-H would then react rapidly with [(R3N)H] + salts to reform compound A. However, the feasibility of this catalytic borylation process is contingent upon (H-BBN)2 undergoing -bond metathesis with NacNacM-Aryl via a low barrier process. This is essential given the endergonic nature of the first step in the putative catalytic cycle, C-H metalation using compound A. This results in an increase in the effective transition state energies for all steps after the C-H metalation. Notably, there are no previously reported studies into the mechanism and associated barriers of the -bond metathesis between (H-BBN)2 and (main group element)-Y species (Y = R, OR, NR2). As (H-BBN)2 exists as a dimer for which dissociation into two equivalents of monomer is significantly endergonic, it is distinct to monomeric boranes, e.g. HBPin/HBCat/HBDan, which could significantly impact the mechanism of the metathesis step.