Compounds that have the formula M(NR)(CHR')(OR '')(Pyrrolide), where OR '' is "large" relative to NR and M = Mo or W, have been shown to be Z-selective olefin metathesis catalysts. In this communication we report a new route to Mo complexes in which the relationship between NR and OR '' has been reversed; i.e., the imido ligand is the sterically demanding 2,6-dimesitylphenylimido ligand (NAr*).