Reactions of (pentamethylcyclopentadienyl)(2,5-dimethylthiophene)iridium with iron carbonyls: a new mechanism for thiophene hydrodesulfurization

Theoretical insight into the desulfurization of thiophene on Pt(110): A density functional investigation

“…The Pt atom is included in the adsorption structure and thus forms a 6-member ring analog. This is similar to the organometallic reaction of thiophene, in which one metal atom inserts into a C S bond [7,32]. The reaction energy is calculated to be −0.02 eV and the activation barrier is 0.51 eV.…”

Desulfurization of Thiophenic Compounds by Ni(111): Adsorption and Reactions of Thiophene, 3-Methylthiophene, and 2,5-Dimethylthiophene

“…38 This mechanism has been proposed in both the catalytic and organometallic literature. This mechanism is not operative in the case of desulfurization on Ni(111) under UHV conditions, where C-S bond scission clearly occurs prior to ring hydrogenation.…”

“…This mechanism, which involves insertion of the metal into the thiophene ring to form a six-membered ring, is entirely analogous to a mechanism observed for an iridium complex. 38 It was found that for CpIr(2,5-dimethylthiophene) the η 4 thiophene structure was readily converted under basic conditions to the six-membered ring structure analogous to that shown in Scheme 1b. These observations lead to a proposal for a new desulfurization mechanism involving C-S bond scission prior to hydrogenation, similar to that proposed in this study.…”

Structure of a ring-opened 2,5-dimethylthiophene complex, (η5C5Me5)Ir(CO)(C,S-Me2C4H2S)

“…The title complex Cp*Ir(CO)(C,S-2,5-Me2T) was isolated (Chen, Daniels & Angelici, 1991) as a by-product from the reaction of Cp*Ir(C,S-2,5-Me2T) with Fe(CO)5 and was identified by its IR and 1H NMR spectra as being the same as that prepared previously (Chen, Daniels & Angelici, 1990a). Crystals were purified from CH2C12/hexane at 193 K. Orange-yellow crystal (0.12 x 0.19 x 0.11 ram).…”