We report ammonia oxidation by homolytic cleavage of all three H atoms from a [Mo-NH3]+ complex using the 2,4,6-tri-tert-butylphenoxyl radical to yield a Mo-alkylimido ([Mo═NR]+) complex (R = 2,4,6-tri-tert-butylcyclohexa-2,5-dien-1-one). Chemical reduction of [Mo═NR]+ generates a terminal Mo≡N nitride complex upon N-C bond cleavage, and a [Mo═NH]+ complex is formed by protonation of the nitride. Computational analysis describes the energetic profile for the stepwise removal of three H atoms from [Mo-NH3]+ and formation of [Mo═NR]+.