A cobalt hydride has been proposed as an intermediate in many reactions of the Co(dmgBF(2))(2)L-2 system, but its observation has proven difficult. We have observed the UV-vis spectra of Co(dmgBF(2))(2)L-2 (1) in CH3CN under hydrogen pressures of up to 70 atm. A Co(I) compound (6a) with an exchangeable proton is eventually formed. We have determined the bond dissociation free energy and pK(a) of the new O-H bond in 6a to be 50.5 kcal/mol and 13.4, respectively, in CH3CN, matching previous reports.