Crystal structure of [3-(2-(N-1H-methylpyrrolidinyl))pyridine]zinc(II) trichloride, Zn(C₁₀H₁₅N₂)Cl₃

Abstract

Source of materialZnCl 2 (1.36 g, about 10 mmol) was added to dimethylacetamid (10 ml) solution, the mixture was stirred at room temperature for 5 . min to obtain acolourless solution. Nicotine (2.ml, 2.02 gand 12.44 mmol) was then added dropwise, and an orange solution was formed. The solution was further stirred for about 20 min, after which alight orange precipitate was observed. The reaction mixture was filtered and the filtrate was then transfered to atest tube and carefully layed by 10 ml i-PrOH. Colourless blockshaped crystals were obtained after 7days. Experimental detailsThe C8 atom is disordered, with two distinct positions. The occupancy for the disordered parts was refined to be 0.45 :0.55. Hydrogen atoms were positioned geometrically and refined using a riding model with d(C-H) =0 .93 -0 .98 Å and U iso (H) =1 .2 U eq (C) [1.5 U eq (C) for the methyl group]. The Flack parameter is 0.000(12) for 1120 Friedel pairs [1]. DiscussionIt is well known that some metal complexes may retain or modulate the biological activity of the organic ligands in some drugs acting via chelation [2] or via the inhibition of metalloenzymes [3]. It is less known about the modification of activity of drugs when their ligating potential is utilized. The interaction of metal atoms, which play avital role in anumber of quite different biological processes, with therapeutically administered drugs is a subject of considerable interest. Several studies on the preparation and characterization of nicotine-metal complexes have been reported. But very little structural information on these compounds is available [4][5][6][7][8][9][10][11][12][13][14]. We have previously reported on crystal structure of the Cu(II) and Hg ( The title compound is aneutral monomeric zinc(II) complex. The zinc atom has adistorted tetrahedral coordination consisting of three chlorine atoms, and the fourth position occupied by the one nitrogen atom of the protonated nicotine molecule. The deviation from tetrahedral geometry is evidenced by the angles N1-Zn1-Cl1 of 104.06(7)°and Cl2-Zn1-Cl1 of 118.81(4)°and with Zn-Cl bond distances between 2.2206(8) . Å and 2.2898(8) .Å.The behaviour of the two N-heterocycle-containing rings of nicotine is completely different. The pyridine ring is coordinated through N1 to aZn(II) ion with N1-Zn1 bond distance of 2.071(2) Å .The pyrrolidine ring is protonated at N2 and does not interact with metal ion, which is different from nicotinemercury(II), -silver(I) and nicotine-copper(II) complexes. In nicotine-copper(II) complexes,the pyrrolidine Na tom is deprotonated. In nicotine-mercury(II) and nicotine-silver(I) compounds, the pyrrolline ring is connected through the deprotonated N2 atom to an another mercury(II) and silver(I) atom and form achain polymeric complexes [6,[11][12][13]. In addition, the absolut configurations of C6 and N2 can be given as S (Snicotine was used as astarting material). There are two kinds of non-typical intermolecular hydrogen bonds between the molecule, one is C4-H4···Cl1 with the donor···...