Reversible CH Bond Activation Reactions of the N-Heterocyclic Carbene Ligands in Ru(Ph2PCH2CH2CH2PPh2)(IMes)(CO)H2 and Ru(Ph2AsCH2CH2PPh2)(IMes)(CO)H2 (IMes=1,3-Dimesityl-1,3-dihydro-2H-imidazol-2-ylidene)

✍ Scribed by Mark J. Chilvers; Rodolphe F. R. Jazzar; Mary F. Mahon; Michael K. Whittlesey

• Publisher: John Wiley and Sons
• Year: 2003
• Tongue: English
• Weight: 118 KB
• Volume: 345
• Category: Article
• ISSN: 1615-4150
• DOI: 10.1002/adsc.200303074

✦ Synopsis

Abstract

Thermolysis of Ru(IMes)(dppp)(CO)H~2~ (1, IMes=1,3‐dimesityl‐1,3‐dihydro‐2__H__‐imidazol‐2‐ylidene; dppp=Ph~2~PCH~2~CH~2~CH~2~PPh~2~) in the presence of trimethylvinylsilane yields Ru(IMes')(dppp)(CO)H (2) resulting from intramolecular ArCH~2~–H CH bond activation of the N‐heterocyclic carbene ligand. The structures of 1 and 2 have been established by X‐ray crystallography. Treatment of Ru(IMes)(arphos)(CO)H~2~ (3, arphos=Ph~2~AsCH~2~CH~2~PPh~2~) with CH~2~CHSiMe~3~ at 85 °C produces a mixture of three CH activated products 4a–c. The CH activated complexes 2 and 4a–c reform their dihydride precursors upon heating under hydrogen.