1H-Tetrazole-5-acetic acid H2tza) can be prepared from ethyl 2-(1H-tetrazol-5-yl)acetate.1H-Tetrazole-5-acetic acid(H2tza) may be used in the preparation of: · 5-(trinitromethyl)-2H-tetrazole · N-(furan-2yl methyl)-2-(1H-tetrazol-5-yl)acetamide · tetrazolium based ionic liquid It may also be used as a bifunctional ligand for the synthesis of novel copper(II) and nickel(II) complexes. 1H-Tetrazole-5-acetic acid H2tza) can be prepared from ethyl 2-(1H-tetrazol-5-yl)acetate.