Insertion of iridium into C-H and C-S bonds of 2,5-dimethylthiophene, 2-methylbenzothiophene and 4,6-dimethyldibenzothiophene

Article abstract of DOI:10.1016/S0022-328X(97)00046-6

C-H insertion thienyl products are selectively formed at early times of the interaction of the unsaturated 16e^- fragment [(triphos)IrH] with 2,5-dimethylthiophene (Me₂T), 2-methylbenzothiophene (MeBT) and 4,6-dimethyldibenzothiophene (Me₂DBT) [triphos = MeC(CH₂PPh₂)₃]. C-S insertion to give six-membered metallathiacycle products occurs as a thermal step only for Me₂T and MeBT. The C-S insertion products are isolated as both kinetic and thermodynamic stereoisomers. The thermodynamic C-S insertion product of MeBT, endo-[(triphos)Ir(η³-S,C,C-S(C₆H₄)CH=C(Me)H)], has been characterized by X-ray diffraction studies.