A series of five 2-heteroarylcyanoximes such as: α-oximino-(2-benzimidazolyl) acetonitrile (HBIHCO), α-oximino-(N-methy-l-2-benzimidazolyl) acetonitrile (HBIMCO), α-oximino-(2- benzoxazolyl) acetonitrile (HBOCO), α-oximino-(2-benzothiazolyl) acetonitrile (HBTCO) and α-oximino-(2-quinolyl) acetonitrile (HQCO) and their monovalent thallium (I) complexes were synthesized and characterized using spectroscopic methods (1H, 13C NMR, IR, UV- ...