Complexes of the type N Mo(OR)(3) (R = tertiary alkyl, tertiary silyl, bulky aryl) have been synthesized in the search for molybdenum-based nitrile-alkyne cross-metathesis (NACM) catalysts. Protonolysis of known N Mo(NMe2)(3) led to the formation of N Mo(O-2,6-(Pr2C6H3)-Pr-i)(3)(NHMe2) (12), N Mo(OSiPh3)(3)(NHMe2) (5-NHMe2), and N Mo(OCPh2Me)(3)(NHMe2) (17-NHMe2). The X-ray structure of 12 revealed an NHMe2 ligand bound cis to the nitrido ligand, while 5-NHMe2 possessed an NHMe2 bound trans to the nitride ligand. Consequently, 17-NHMe2 readily lost its amine ligand to form N Mo(OCPh2Me)(3) (17), while 12 and 5-NHMe2 retained their amine ligands in solution. Starting from bulkier tris-anilide complexes, N Mo(N[R]Ar)(3) (R = isopropyl, tert-butyl; Ar = 3,5-dimethylphenyl) allowed for the formation of base-free complexes N Mo(OSiPh3)(3) (5) and N Mo((OSiPh2Bu)-Bu-t)(3) (16). Achievement of a NACM cycle requires the nitride complex to react with alkynes to form alkylidyne complexes; therefore the alkyne cross-metathesis (ACM) activity of the complexes was tested. Complex 5 was found to be an efficient catalyst for the ACM of 1-phenyl-1-butyne at room temperature. Complexes 12 and 5-NHMe2 were also active for ACM at 75 degrees C, while 17-NHMe2 and 16 did not show ACM activity. Only 5 proved to be active for the NACM of anisonitrile, which is a reactive substrate in NACM catalyzed by tungsten. NACM with 5 required a reaction temperature of 180 degrees C in order to initiate the requisite alkylidyne-to-nitride conversion, with slightly more than two turnovers achieved prior to catalyst deactivation. Known molybdenum nitrido complexes were screened for NACM activity under similar conditions, and only N Mo(OSiPh3)(3)(py) (5-py) displayed any trace of NACM activity.