Mechanism of S_H2 Reactions of Disulfides: Frontside vs Backside,Stepwise vs Concerted

摘要

Density functional theory calculations indicate that the S_H2 reactions of disulfides with alkyl or arylradicals take place via concerted backside displacement. The activation energies for reactions of Mewith RSSR (R = Me, Et, ~tPr, tBu) increase with the size of R, since larger R groups prevent theformation of an ideal geometry for SOMO-LUMO overlap. Frontside transition states can also belocated, but these lie at least 11 kcal mol~(-1)