Trapping and crystallographic characterization of Valsartan intermediate (tetrazole-zinc complex)

4'-Methylbiphenyl-2-tetrazole (HMBT) is an important intermediate to the synthesis of Valsartan while HMBT is obtained by the decomposition of Zn-complex (organic-inorganic polymer) containing HMBT. This is the first example of crystallographic characterization of Zn-complex with HMBT produced during in situ [2+3] cycloaddition between 4-methylbiphenyl-2-carbonitrile (MBC) and NaN3 in the presence of ZnCl2. Also, crystal structural determinations of HMBT and impurity produced during hydrothermal hydrolysis reaction of MBC were reported. (C) 2008 Published by Elsevier B.V.