Substituted 2, 2'-biindazoles 4 and 19-23 were prepared in W90% yields by thermal decomposition of o, o'-diazido azines 13-18, which in turn were readily obtained from the corresponding 2-azidobenzaldehydes or 2-azidobenzophenones. The preference of these N, N'-linked azolyl dimers for an almost orthogonal conformation was clearly demonstrated by the strong deshielding of the H-3 signal in'H NMR spectra. Appropriate substituted ...
