ISSN:
1573-1111
Keywords:
Dioxocyclam
;
5,7-dioxo-1,4,8,11-tetra-azacyclotetradecane
;
platinum tetrachloride
;
crystal structure
;
paramagnetic properties of ionic stacked structure
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Abstract The paramagnetic complex salt of diprotonated dioxocyclam (1,11-dihydro-5,7-dioxo-1,4,8,11tetra-azacyclotetradecane), Pt(II) tetrachloride and water has been synthesized in strongly acidic medium and identified by X-ray structure analysis. The crystals of [(C10H22N4O2)2+(PtCl4)2−]·H2O are monoclinic, space groupP21 c,M r=585.23,a=9.516(1) Å,b=11.926(1) Å,c=16.622(2) Å,β=102.88(2)°,V=1839(1)Å3,Z=4,D x=2.114 g cm−3, λ(MoK α)=0.70930 Å,μ=83.1 cm−1,F(000)=1128,T=292 K,R=0.019 for 2808 observed reflections withI 〉 3δ(I). Alternating moieties of diprotonated dioxocyclam and a PtCl 2− 4 anion form columns running down the c axis. Water molecules are localized in the intercolumnar space and contribute to the extensive hydrogen bond network. The macrocycle conformation is characterized by two sequences of torsional angles, corresponding to two different subunits. The shorter sequence idealized as (-sc, ap, -ac, + ac, ap, +sc) [sc( ±60°), ac( ±120°), ap(180°)], describing the C pseudosymmetric part of the molecule, is centered on a -CH2 group between the two peptide O-C-N-H fragments. The opposite C pseudosymmetric subunit has a nearly (-sc, ac, -SC, ap)2 conformation. Pt is square planar coordinated by four Cl atoms, Pt-Clαve = 2.306(8) Å. The shortest Pt ... Pt distance is 7.200(1) Å.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01053643
