Matrix isolation study of the interaction of HCl with CrCl2O2 and OVCl3

1:1 hydrogen bonded complexes of HCl with CrCl2O2 and OVCl3 have been isola ted in argon matrices and characterized by infrared spectroscopy. For both complexes, the H-Cl stretching mode was observed, shifted 52 and 47 cm(-1), respectively, from parent HCl. Deuterium substitution, leading a nu(H)/nu( D) ratio = 1.38, verified the identification and band assignment. For the O VCl3. HCl complex, the shifted V=O 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 c omplexes and represents approximately a 3.5% decrease in the H-Cl stretchin g force constant. These results suggest that the initial step in the oxidat ion of many organic substrates containing a heteroatom and an acidic hydrog en (e.g. CH3OH) may be coordination of the substrate to the transition meta l center rather than a hydrogen bonding interaction with the oxo group. (C) 2000 Elsevier Science B.V. All rights reserved.