An Organic Channel Structure Formed by the Supramolecular Assembly of

An organic channel structure formed by the supramolecular assembly of trithiocyanuric acid and 4,4 -bipyridyl CO CD 

Chemistry Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur P. O., Bangalore 560 064, India  

Trithiocyanuric acid (TCA) and 4,4 -bipyridyl (BP) form hydrogen-bonded co-crystals with aromatic compounds such as benzene, toluene, /7-xylene and anthracene. The TCA-BP co-crystal is composed of cavities formed by the N-H - N hydrogen bonds between the two molecules, and the three-dimensional structure contains channels of approximately 10 A where aromatic molecules are accommodated. The molar ratios of TCA, BP and the aromatic compound in the co-crystals are 2 1 1 or 2 1 0.5. Benzene, toluene and /7-xylene are removed from the channels around 190, 183 and 170 °C respectively, and these aromatic guests can be reintroduced into the empty channels of the apo-hosts. The apo-hosts with empty channels have reasonable thermal stability and exhibit shape selectivity in that the empty channels accommodate /7-xylene but not m- or o-xylene or mesitylene. 

Crystals of 1-6 prepared as above were employed for the determination of molecular structure by single crystal X-ray diffraction. The relevant details of the crystal structures of the co-crystals are listed in Table l.f The intensity data were collected on a SMART system, Siemens, equipped with a CCD area detector,13 using Mo-Koc radiation. The structures were solved and refined using SHELXTL14 software. The refinements were uncomplicated and converged to good R-factors as 

Formulae 2(C3H3N3S3) 2(C3H3N3S3) 2(C3H3N3S3) 2(C3H3N3S3) 2(C3H3N3S3) 2(C3H3N3S3)  

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