Matrix isolation study of the reaction of dimethyl sulfoxide with CrCl2O2 and OVCl3

The matrix isolation technique, combined with infrared spectroscopy and theoretical calculations, has been employed to investigate the thermal and photochemical reactions of dimethylsulfoxide (DMSO) with CrCl2O2 and OVCl3. Twin jet codeposition leads to formation and isolation of a photochemically unstable 1:1 complex. The photoproduct in the twin jet DMSO + CrCl2O2 experiments is identified as dimethyl sulfone, (CH3)2SO2, interacting with the Cl2CrO fragment, while in the analogous OVCl3 reaction, the photoproduct bands were too weak to allow product identification. Merged jet codeposition led to rapid gas phase reaction, and in the case of DMSO + CrCl2O2, dimethyl sulfone is formed in high yield. This marks the first demonstration of a gas phase thermal oxygen atom transfer from CrCl2O2 to an organic substrate. For the reaction of DMSO with OVCl3, no volatile products are deposited in the matrix and dimethyl sulfone is not a product. These results support differing pathways for the reactions of CrCl2O2 and OVCl3, a conclusion that is supported by density functional calculations