| Abstract: | Template reactions of salicylaldehyde or pentanedione with 3-aminopropanethiol (Hapt) in the presence of Ni(II) ions are described. When salicylaldehyde was used, a dinuclear Ni(II) complex Ni(bit′)]2 (2) (H2bit′?=?2-(3′-mercaptopropyliminomethyl)phenol) was obtained instead of the reported trinuclear one Ni(bit)]3 (1) (H2bit?=?2-(2′-mercaptoethyliminomethyl)phenol) containing 2-aminoethanethiol (Haet). Starting from pentanedione, the expected dinuclear complex Ni(pit′)]2 (H2pit′?=?2-(3′-mercaptopropylimino)pentanol) was not obtained, nor was Ni(pit)]2 (3) (H2pit?=?2-(2′-mercaptoethylimino)pentanol). The complex was found to be a trinuclear Ni(II) complex Ni{Ni(apt)2}2]2+ (4), as confirmed by elemental analysis, electronic and NMR spectra. Complexes 1 and 3 were also synthesized and their 13C, 1H–1H and 13C–1H?NMR spectra are discussed in detail. The X-ray crystal structure of 2 shows that two Ni(II) ions are connected by the thiolate donor atom from each ligand, resulting in a four-membered ring. Differences in reactivity and properties is due to the presence of an additional methylene group in the aminoalkane arm of the ligand. |
