Crystal structure of quininium-trichloro-zinc(II), ZnCl3(C20H25N2O2), C20H25Cl3N2O2Zn

Junghwan Do, et al.
2013 Zeitschrift für Kristallographie - New Crystal Structures  
C 20 H 25 Cl 3 N 2 O 2 Zn, orthorhombic, P2 1 2 1 2 1 (no. 19), a =7.673(2) Å, b =11.485(2) Å, c =24.655(5) Å, V =2172.6 Å 3 , Z =4,R gt (F) =0.0487, wR ref (F 2 ) =0.1381, T =296 K. Source of material Thet itle complex was synthesized from am ixture of ZnCl 2 (0.123g, 0.90mmol), quinine (0.097g, 0.30 mmol) and ethanol (1.0 ml), which was sealed in aPyrex tube and heated to 100 °C for 68 h, then cooled to room temperature at 10 °C/h. The solid products were recovered by vacuum filtration and
more » ... hed with distilled water. Colourless rod-like crystals were obtained with unidentified yellow powder. The product was stable in air. The yield of the compound was about 48 %based on zinc. EDS analysis confirmed the presence of Zn and Cl. Experimental details All the hydrogen atomsa ssociated with the quininium cation were placed geometrically andrefined as riding. TheFlack parameter was 0.00(3). Discussion Cinchona alkaloids have been intensively studied due to their usages in antimalarial treatments and asymmetric synthesis as powerful chiral auxiliaries [1] . There are more than 30 Cinchona alkaloidsextracted from the Cinchona tree,and amongthemthe most important molecules are quinine, quinidine, cinchonine, cinchonidine, and their threo epimers. Depending on the absolute configurations of the Cinchona alkaloids, the biological activities in the antimalarial action are different. This implies that the reaction of Cinchona alkloids andametal cation in apotential receptor possibly hematin mayh ave ab ig impact on antimalarial actions. To understand this clearly, structural studies are required and several trichlorocobalt(II)complexes of quinine, cinchonine, quinidine, cinchonidine, epiquinine, epiquinidine, and epidihydrocinchonine have been reported [2] [3] [4] [5] . The crystal structure of the title compound comprise ad iscrete noncentrosymmetric mononuclear ZnCl 3 (Hquinine) molecule. One crystallographically unique Zn atom is coordinated by one nitrogen atom (d(Zn-N) =2.087(6) Å) in aprotonated quininium cation and three chlorine atoms(d(Cu-Cl) =2.246(2) Å, 2.250(2) Å, 2.272(2) Å) in atetrahedral geometry. This compound is aso called,"zwitterion", wherethe positive charge is localized at the protonated nitrogen atom of quinuclidine moiety and the negative charge in the vicinity of three chlorine atoms. The absolute configuration of the diasteroisomer, quinine is S and R for C12 and C11, respectively. Abond valence sum (BVS) calculation of Zn gives avalue of +1.97, indicating an oxidation state of +2 [6] . The ZnCl 3 (Hquinine) molecules are weakly hydrogen bonded to each other throughD-H•••Cl(D=C,N,O)inacomplexarrangement.
doi:10.1524/ncrs.2013.0035 fatcat:n6ebsscupbcuzbl4ase2ahck4u