Abstract: | We synthesized Mo(NC 6F5)(CHCM e2Ph)(TPPO )(PP hMe2)Cl (TPPO = 2,3,5,6‐tetraphenylphenoxide), Mo(NC 6F5)(CHCM e2Ph)(TTBTO )(PP hMe2)Cl (TTBTO = 2,6‐di(3′,5′‐di‐tert‐butylphenyl)phenoxide), and Mo(NC 6F5)(CHCM e2Ph)(TPPO )(PP hMe2)(CF 3Pyr) (CF 3Pyr = 3,4‐bistrifluoromethylpyrrolide), in order to evaluate them as catalysts for the homocoupling of 3‐methyl‐1‐butene. They were compared with Mo(NC 6F5)(CHCM e2Ph)(HMTO )(PP hMe2)Cl (HMTO = 2,6‐dimesitylphenoxide), Mo(NC 6F5)(CHCM e2Ph)(HIPTO )(PP hMe2)Cl (HIPTO = 2,6‐di(2′,4′,6′‐triisopropylphenyl)phenoxide), and several other Mo and Ru catalysts. In the best cases turnover numbers (TON s) of 400 – 700 were observed for the homocoupling of 3‐methyl‐1‐butene in a closed vessel (ethylene not removed). |