Department of Chemistry, B.N.M.A. College, Paliabindha, Bhadrak-756 167, India E-mail : nayaksarat@yahoo.com P.G. Department of Chemistry, Bhadrak College, Bhadrak-756 100, India Department of Chemistry, F. M. College, Balasore-756 00 1, India Manuscript received 25 October 2002, revised 10 July 2003, accepted 2 December 2003 A series of new hydrogen bonded trαns-azidocobaloxirne of the type [Co(DH)2N3L] where DH = dimethylglyoximato anion, L =[pyridine, piperidine, piperazine, quinoline, iso-quinoline, triazole, indole, benzimidazole, benzotriazole, or carbazole] have been prepared by passing air in cobalt(ll) acetate, sodium azide, dimethylglyoxime and heterocyclic nitrogen donor ligands in ethanol medium. The complexes are characterized by UV, IR, NMR spectra. The thermogravimetric analyses indicate that these compounds are quite stable upto 200° and never associated with solvent or water molecules.