Solution and Solid-State Structure of cis-Dichloro-(N,N′-dimethylethylenediamine)platinum(II)

Autor: Devin Oliver, Steven M. Drew, Daron E. Janzen, SaeRam Oh, Elijah Mae Christensen
Rok vydání: 2014
Předmět:
Zdroj: Journal of Chemical Crystallography. 44:236-242
ISSN: 1572-8854
1074-1542
Popis: The chiral coordination compound cis-dichloro-(N,N′-dimethylethylenediamine) platinum(II) (Pt(dmen)Cl2) has been synthesized and characterized by NMR and X-ray crystallography. NMR studies in d 6 -DMSO solution reveal distinct resonances are observed for the equatorial and axial methylene protons leading to the conclusion that Pt(dmen)Cl2 is found as one stereoisomer and one conformer of the five-membered ring formed by the Pt2+ and dmen ligand. In D2O NMR evidence also suggests one stereoisomer and one conformer dominates in aqueous solution. Crystallographic studies indicate the presence of the R,R′/S,S′ stereoisomer with a λ conformation of the Pt2+-dmen five-membered ring. This implies that the stereoisomer and conformer observed in d 6 -DMSO and D2O solution are likely the same. The crystal structure of Pt(dmen)Cl2 has the unusual feature of homochiral one-dimensional stacks of R,R′-Pt(dmen)Cl2 and S,S′-Pt(dmen)Cl2. Structure of Pt(dmen)Cl2: monoclinic, P 21/c, a = 7.491(2) A, b = 16.356(4) A, c = 14.503(3) A, β = 103.636(8)°, V = 1726.8(7) A3, Z = 8, GOF = 1.121, R 1 = 0.0514, wR 2 = 0.1298. cis-Dichloro-(N,N′-dimethylethylenediamine)platinum(II) forms a racemic mixture of the S,S′ and R,R′ enantiomers in solution as well as in the solid state where the crystalline packing is characterized by homochiral stacks.
Databáze: OpenAIRE
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