ORIGINAL PAPER Synthesis and Structural Chemistry of a Ternary Calix[4]arene Lattice Inclusion System Solhe F. Alshahateet Received: 2 July 2008 / Accepted: 12 September 2009 / Published online: 1 October 2009 Ó Springer Science+Business Media, LLC 2009 Abstract A ternary calix[4]arene lattice inclusion system 3 has been synthesized, characterized and its crystal structure was determined by single crystal X-ray diffrac- tion study. 3 is orthorhombic, space group Pbca with a = 21.236(3) A ˚ , b = 12.2820(16) A ˚ , c = 25.795(3) A ˚ , a = 90°, b = 90°, c = 90° and Z = 4. Analyses of single crystals of arene 3 crystallized from DMSO revealed the existence of a ternary system of 3 with DMSO and H 2 O. Compound 3 exists in eclipsed form rather than the stag- gered form. Different types of host–host, host–guest and guest–guest interactions were observed and analysed. Keywords Acid-catalyzed Á Host–guest chemistry Á Supramolecular chemistry Á Eclipsed isomer Á Staggered isomer Á X-ray crystal structure Introduction Calix[4]arenes are macrocyclic molecules formed from phenolic units supporting various substituents and bridged by methylene groups. These materials have found many applications [1–10]. For example, in the area of drug delivery, Coleman et al. [11, 12] have reported that p-sulfonatocalix[n]arenes show no haemolytic effects or toxicity and did not provoke immune reactions compared to cyclodextrins, which show unfavourable haemolytic properties. These observations provide promising signs that calix[4]arenes could be used in pharmaceuticals industry. By making use of molecular recognition properties, they can be tailored to allow targeting of biological receptors. In host–guest chemistry, Ma et al. [13] reported on several crystal structures of benzil in calix[4]resorcinarene host matrixes to explore the influence of the host environment on the properties of the guest benzil. There is also work done to synthesize calix[4]arenes as host molecules with chiral recognition [14]. Recently, we are interested in designing new systems of calix[4]arenes and to explore their ability as potential host molecules for future industrial applications. Our research strategy involves investigating the effect of temperature, substituent type and position at the benzene ring on the formation of different isomers and hence exploring the supramolecularity of each isomer. The variation of the reaction temperature played a crucial factor in the struc- tural conformation of the formed isomers [15]. In this paper, we present the synthesis and the solid state structure analyses of C-phenylcalix[4]pyrogallolarenes under three different reaction temperatures; ice, room and reflux temperatures. Experiments Reagent grade chemicals were used directly without further purification. The crystal structure of compound 3 was determined using Bruker Smart-1000 CCD Diffractometer instrument. Synthesis of C-Phenylcalix[4]Pyrogallolarene Host C-Phenylcalix[4]Pyrogallolarene was synthesized as shown in Scheme 1 [15]. A solution of benzaldehyde 1 (1 equiv- alent) in ethanol was added dropwise to an ice-cooled solution of pyrogallol 2 (1 equivalent) in a mixture of S. F. Alshahateet (&) Department of Chemistry, Faculty of Science, Mutah University, P.O. BOX 7, Mutah, Al-Karak 61710, Jordan e-mail: s_alshahateet@mutah.edu.jo 123 J Chem Crystallogr (2010) 40:191–194 DOI 10.1007/s10870-009-9632-y