Kinetics of sulfur-transfer from titanocene (poly)sulfides to sulfenyl chlorides: rapid metal-assisted concerted substitution.

ABSTRACT: The kinetics of sulfur transfer from titanocene (poly)sulfides (RCp2TiS5, Cp2TiS4CMe2, Cp2Ti(SAr)2, Cp2TiCl(SAr)) to sulfenyl chlorides (S2Cl2, RSCl) have been investigated by a combination of stopped-flow UV-Vis/NMR reaction monitoring, titration assays, numerical kinetic modelling and KS-DFT calculations. The reactions are rapid, proceeding to completion over timescales of milliseconds to minutes, via a sequence of two S-S bond-forming steps (k1, k2). The archetypical polysulfides Cp2TiS5 (1a) and Cp2TiS4C(Me2) (2a) react with disulfur dichloride (S2Cl2) through rate-limiting intermolecular S-S bond formation (k1) followed by a rapid intramolecular cyclization (k2, with k2 ≫ k1 [RSCl]). The monofunctional sulfenyl chlorides (RSCl) studied herein react in two intermolecular S-S bond formi

SUBMITTER: Helou de Oliveira PH 

PROVIDER: S-EPMC11290412 | biostudies-literature | 2024 Jul

REPOSITORIES: biostudies-literature