Reactions of ruthenium hydrides with ethyl-vinyl sulfide

Abstract

The Ru-hydride precursors (Im(OMe)₂)(PPh₃)₂RuHCl (1) and (Me₂Im(OMe)₂)(PPh₃)₂RuHCl (2) reacted with ethyl-vinyl-sulfide to give ((MeOCH₂CH₂)C₃H₂N₂(CH₂CH(OMe))RuCl(PPh₃)₂ (3) and ((MeOCH₂CH₂)C₃Me₂N₂(CH₂CH(OMe))RuCl(PPh₃)₂ (4), respectively. Dissolution of (4) in C₆D₆ prompts formation of ((MeOCH₂CH₂)C₅H₆N₂(CHCH)RuCl(PPh₃)₂ (5). The analogous reactions of the bis-carbene Ru-hydride precursors (Im(OMe)₂)(IMes)(PPh₃)RuHCl (6), (Im(OMe)₂)(SIMes)(PPh₃)RuHCl (7) and (Im(OMe)₂)(IMes-Cl₂)(PPh₃)RuHCl (8) gave ((MeOCH₂CH₂)C₃H₂N₂(CHCH)RuCl(PPh₃)(NHC) (NHC = IMes (9), SIMes (10), IMes-Cl₂ (11), respectively. The formation of compounds (3–5) and (9–11) is thought to go through an initial insertion of the vinyl-fragment into the Ru–H prompting subsequent C–H activation and loss of diethyl sulfide. This yields (3) and (4), while subsequent loss of methanol yields (5) and (9–11).