ISSN print edition: 0366-6352
ISSN electronic edition: 1336-9075
Registr. No.: MK SR 9/7
N,N′-methylenedipyridinium Pt(II) and Pt(IV) hybrid salts: synthesis, crystal and molecular structures of [(C5H5N)2CH2] · [PtCl4] and [(C5H5N)2CH2] · [PtCl6]
Mahmoud M. Al-Ktaifani and Mwaffak K. Rukiah
Department of Chemistry, Atomic Energy Commission, P.O. Box 6091, Damascus, Syria
Abstract: The highly insoluble organic-inorganic hybrid ionic compounds N,N′-methylenedipyridinium tetrachloroplatinate(II) [(C5H5N)2CH2] · [PtCl4] and N,N′-methylenedipyridinium hexachloroplatinate(IV) [(C5H5N)2CH2] · [PtCl6] were obtained by the treatment of N,N′-methylenedipyridinium dichloride monohydrate [(C5H5N)2CH2]Cl2 · H2O with K2[PtCl4] or (NH4)2[PtCl6], respectively, in an aqueous solution. Both complexes were isolated, purified, characterised by elemental analysis, and
their molecular structures were confirmed by powder X-ray diffraction. The crystal structure of both compounds consists of
separated discrete dications [(C5H5N)2CH2]2+ and anions [PtCl
]2− (n = 4 or 6). As anticipated, the dications formed a butterfly shape consisting of two pyridine rings bound to the methylene
group via their N atoms, while the Pt centre had a square planar geometry in [(C5H5N)2CH2] · [PtCl4] and an octahedral coordination in [(C5H5N)2CH2] · [PtCl6]. Interestingly, both crystal structures are stabilised by intermolecular C-H…Cl non-standard hydrogen bonds, π-π ring interactions between two pyridine rings of adjacent dications, and also by Cl-π interactions.
Keywords: dications – N,N′-methylenedipyridinium – organic-inorganic hybrid salt – powder X-ray diffraction – Pt complex
Full paper is available at www.springerlink.com.
Chemical Papers 66 (11) 1032–1038 (2012)