1:1 hydrogen bonded complexes of HCl with CrCl2O2 and OVCl3 have been isolated in argon matrices and characterized by infrared spectroscopy. For both complexes, the H–Cl stretching mode was observed, shifted 52 and 47cm−1, respectively, from parent HCl. Deuterium substitution, leading a νH/νD ratio=1.38, verified the identification and band assignment. For the OVCl3·HCl complex, the shifted VO stretching mode was observed, suggesting that the site of interaction for the hydrogen bond is with the oxo group. The shift of the H–Cl stretching mode is quite small compared to many HCl complexes and represents approximately a 3.5% decrease in the H–Cl stretching force constant. These results suggest that the initial step in the oxidation of many organic substrates containing a heteroatom and an acidic hydrogen (e.g. CH3OH) may be coordination of the substrate to the transition metal center rather than a hydrogen bonding interaction with the oxo group.