Aluminum Atom Activation of C-S Bonds: An EPR Study of the Intermediates Formed in the Reaction Between Aluminum Atoms and Dialkyl Sulfides.

Abstract

The major mononuclear aluminum species obtained in the reaction of aluminum atoms with dimethyl sulfide (DMS) and diethyl sulfide (DES), under cryogenic conditions, are the C-S insertion products, CH3AlSCH3 and CH3CH2AlSCH2CH3, respectively, showing that aluminum atoms can activate C-S bonds. The magnetic parameters were extracted from the EPR spectrum. Support for the spectral assignment was obtained by repeating the experiments with 13C-labeled dimethyl sulfide yielding 13CH3AlS13CH3. DFT calculations using the M06 functional have proven to be effective in predicting the isotropic and anisotropic Al hyperfine interaction values of the aluminum atom C-S insertion products. In addition, the thioalkyl radicals, CH3SCH2• and CH3CH2SCH•CH3 were formed in the aluminum atom reaction.