Synthesis and crystal structure of a ternary lattice inclusion system of C-4-acetamidophenylcalix[4]-2-methylresorcinarene dimethylsulfoxide tetrasolvate dihydrate

Abstract

C-4-acetamidophenylcalix[4]-2-methylresorcinarene was synthesized by condensation reaction of 2-methylresorcinol with 4-acetamidobenzaldehyde in the presence of concentrated HCl. The compound was characterized by infrared (IR), 1H, and 13C NMR spectroscopy. Single crystal X-ray analysis revealed that the molecule crystallized in a triclinic crystal system with space group of Pi¯ and the unit cell dimensions are a = 8.929(1) Å, b = 13.804(2) Å, c = 14.471(2) Å, α = 76.766(4)°, β = 78.563(4)°, γ = 87.168(4)°, Z = 1, and V = 1702.0(4) Å3. The calix molecule is associated with four dimethylsulfoxide (DMSO) and two water molecules of crystallization that contribute to the stability of the solid via hydrogen bonding. The supramolecule adopts a chair (C2h) conformation with four phenyl linkage groups that are in rctt (cis-trans-trans) configuration isomer. The thermal gravimetric investigation showed three mass loss steps that occurred at about 100, 400, and 900 °C, respectively. The compound formed after the first loss is thermally stable in the range of 100-400 °C after which the calix moiety began to decompose.