Coordination studies of copper(II), nickel(II), cobalt(II) and zinc(II) salts with pyridyl–tetrazole ligands containing alkyl or alkyl halide pendant arms

Abstract

a b s t r a c tThe reaction of 2-(2H-tetrazol-5-yl)pyridine (L1) with 1,n-dibromoalkane (n = 3, 4, 6 or 8) results in the formation of the isomers 2-(n 00 -bromoalkyl-(1-tetrazol-5-yl)pyridine (L2A-D) and 2-(n 00 -bromoalkyl-(2-tetrazol-5-yl)pyridine (L3A-D). The reaction of L1 with 1-bromoalkanes also resulted in the formation of isomeric materials, namely 2-(n 00 -alkyl-(1-tetrazol-5-yl)pyridine (L4A-C) and 2-(n 00 -alkyl-(2-tetrazol-5-yl)pyridine (L5A-C). Complexation reactions of these ligands with the transition metal salts CuCl 2 Á2H 2-O, Co(NCS) 2 , NiCl 2 Á2H 2 O and ZnCl 2 were carried out in methanol and resulted in complexes containing a 1:1 metal:ligand stoichiometry except in the cases of the cobalt complexes where a 1:2 metal:ligand stoichiometry was obtained. The 1 H NMR spectra of the zinc complexes showed that the ligands containing the pendant arm in the 2-N position of the tetrazole ring bind the zinc ion more strongly than those containing the pendant arm in the 1-N position. The X-ray structures of two cobalt salts, Co(L5A) 2 (NCS) 2 and Co(L5C) 2 (NCS) 2 , are also discussed.

Selectivity control towards CO versus H2 for photo-driven CO2 reduction with a novel Co(II) catalyst

“…The nitrogen atoms of the two quinoline moieties are therefore trans to each other. This conformation might be induced by the cobalt precursor Co(NCS) 2 (py) 4 , which has already the NCS monodentate ligands cis to each other, as it was not the case for other Co(NCS) 2 (NN) complexes, where NN is a chelating diimine compound such as pyridyl-tetrazole [44], or a pyridine-oxazole [45]. The bond lengths are very similar when comparing the polymorphs 1a and 1b.…”

2,6‐Di(1H‐tetrazol‐1‐yl)pyridine and its cupric chloride complex

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14] Since the nature and position of substituents in the tetrazole ring make a significant contribution to the variety of structural features and properties of tetrazole-containing complexes, [1] tetrazole derivatives, in which the substituent can also be coordinated by metal ions, in particular, pyridyltetrazoles are of interest as objects for research. In contrast to 5pyridyltetrazoles, whose coordination chemistry has been well studied, [15][16][17][18][19][20][21][22][23][24][25][26][27] only one publication [28] is devoted to complexation of 1-pyridyltetrazoles.…”