Under strictly anhydrous conditions, no reaction occurs between Mo-2(O2CCMe3)(4) and tetracyanoethylene, TCNE, at room temperature, but after addition of 1 equiv of water, a reaction proceeds to form [Mo-2(O2CCMe3)(3)((NC)(2)CC(CN)CONH)], 1. The compound contains a quadruple-bonded MO2 unit and the 2,3,3-tricyanoacrylamidate anion as a ligand (TC3A), a very unusual hydrolyzed form of TCNE. Two different solid-state structures were obtained after crystallization of 1. Crystals obtained from CH2Cl2 consist of a two-dimensional network, and crystals grown from a C6H6 solution form a 1-D chain motif. In both cases, the TC3A ligand acts as a polydentate ligand involving a bidentate OCN bridging unit and two CN groups. The electrochemical and spectroscopic (IR, UV/vis/near-IR, NMR, EPR) properties of 1 support the formulation in solution as a discrete 1:1 complex of the TC3A donor ligand and a Mo-2 unit with no charge transfer. The coordinated TC3A ligand exhibits redox properties similar to those of free TCNE.