Bis-(S-benzylthiuronium) chloranilate supramolecular crystal structure: Preparation and characterization

This item is provided by the institution :
University of Ioannina
Repository :
Repository of UOI Olympias
see the original item page
in the repository's web site and access all digital files if the item*

2005 (EN)
Bis-(S-benzylthiuronium) chloranilate supramolecular crystal structure: Preparation and characterization (EN)

Stergiou, D. V. (EN)

Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας (EL)
Stergiou, D. V. (EN)

A novel supramolecular structure, [C8H11N2S](2)center dot(C6Cl2O4), based on hydrogen bonding of the organic S-benzylthiuronium (SBT) cation and the chloranilate dianion, is presented. Chloranilic acid or 2,5-dichlro-3.6-dihydroxy-1,4-benzoquinone, is a strong quinoidal diphenic acid (pK(1) = 1.09 and pK(2) = 2.42), with molecular formula C6Cl2O4H2 (H(2)CA). The CA-dianions and the aromatic rings of the SBT-cation; form columns along the c-axis giving an ordered pattern of dianions surrounded by densely populated areas of SBT-cations. Each CA-dianion forms eight hydrogen bonds with the amine protons of six SBT-cations, through its oxygen atoms. In this way, an extended H-bond network, containing infinite chains of alternative R-4(2)(8) and R-2(2)(9) cyclic patterns, is obtained. The whole arrangement leads to a C2/c space group crystal structure, with unit cell dimensions a = 15.109 angstrom, b = 11.606 angstrom, and c = 14.390 angstrom and with unit cell angles of alpha = gamma = 90 degrees, and beta = 97.01 degrees, and average density of 1.43 g/cm(3). Dissolution of the crystalline material in DMSO leads to the formation of associated organic ions or charge-transfer complexes as evidenced from the bathochromic shift of the absorption band of chloranilic acid from 420 to 520 nm. (EN)

complexes (EN)

Πανεπιστήμιο Ιωαννίνων (EL)
University of Ioannina (EN)

Chemistry of Materials (EN)



<Go to ISI>://000227772100011

*Institutions are responsible for keeping their URLs functional (digital file, item page in repository site)