Addition of a 2M solution of NH3 in ethanol to solid tetraaquabis(propynoato)zinc 1 leads directly to the title complex 2, Formation of hydroxides is eliminated using this procedure. The structure of 2 differs markedly from the octahedral structure observed for the analogous octahedral aqua complex 1, The structure of 2 is monomeric and tetrahedral, with monodentate carboxylate ligands. The crystal structure consists of isolated molecules interconnected by two strong N-H . . .O hydrogen bonds and one C-H . . .O hydrogen bond. Infinite sets of short -C=C- . . . -C=C- contacts are also present in the crystal structure. Accordingly. Co-60 gamma -irradiation of 2 leads to the analogous dark brown polypropynoate complex.