Synthesis and crystal structure of the first complex derived from a quinolyl substituted 1,2,4-triazole

A new quinolyl substituted 1,2,4-triazole, 3-(p-methylphenyl)-4-phenyl-5- (2- quinolyl)-1,2,4-triazole (L) and its iron(II) complex cis-[FeL ₂(NCS)₂] (1), have been successfully synthesized and characterized by single-crystal X-ray diffraction. Both L and 1·Me ₂CO crystallize in monoclinic system but with different space groups: P21/c for L and C2/c for 1·Me₂CO. The L molecule is nonplanar and intermolecular C-H···N hydrogen bonds link two L molecules to form a dimer, which is further connected by intermolecular C-H···p interactions to produce 1D chains along the c axis. In complex 1·Me₂CO, the iron(II) cation lies in a distorted octahedral environment with two cis-disposed NCS- ions. The L ligand coordinates via one triazole nitrogen and the quinolyl nitrogen. There is an intermolecular offset face-to-face p···p stacking interaction in the crystal packing of 1·Me₂CO. 1 is the first complex with a quinolyl substituted 1,2,4-triazole.