Synthesis and Solid-State Structure Analyses of a Thia-Bridged Diquinolinium Acetate Compound

The proton-transfer compound of thia-bridged dinitrodiphenyldiquinoline 4 with acetic acid was obtained through crystallization of compound 3 from acetic acid. Solid-state structure of 4 was determined by single-crystal X-ray diffraction. Compound 4 was ionic, with proton transfer occurring from one acetic acid hydroxy group to the aromatic nitrogen of one of the pyridine moiety leaving the other one unprotonated. The versatile supramolecular self-assembly of 4 was carefully investigated and presented in term of crystal engineering and host-guest chemistry, interesting synthons including different motifs of hydrogen bonding, ion-pairing interactions were observed. Compound 4 crystallized in the triclinic space group P-1. The unit cell parameters were a = 8.9318(4) Å, b = 10.7353(5) Å, c = 17.3942(8) Å, with α = 87.0800(10)°, β = 87.6850(10)°, γ = 86.1640(10)° and with a final R value of 0.0848.