Structure and Peculiarities of ¹H NMR‐Spectra of Palladium(II) Complexes with 3‐(2‐pyridyl)‐5‐Alkyl‐1,2,4‐triazoles

A series of chelating N N proligands, 3‐(2‐pyridyl)‐5‐alkyl‐1,2,4‐triazoles (HL Alk ), where alkyl=methyl, ethyl, isopropyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl was used as building blocks for designing of coordination compounds. Their reaction with an equimolar amount of [PdCl 2 (CH 3 CN) 2 ] led to formation of series of six novel palladium complexes [Pd(HL Alk )Cl 2 ], in which ligands are coordinated in the acid form. New proligands and Pd(II) complexes were characterized by IR, 1 H and 13 C NMR spectroscopy and elemental analysis. The Pd(II) complexes showed an unusual downfield shift in 1 H NMR of the aliphatic proton that is the closest to triazole ring, which suggests the C−H…Cl hydrogen bonding, supported by X‐ray data for Pd(HL c− Pr )Cl 2 and Pd(HL c− Bu )Cl 2 .