Thermochemistry of phenols: experimental standard molar enthalpies of formation of 2-phenylphenol, 4-phenylphenol, 2,6-diphenylphenol, and 2,2′- and 4,4′-dihydroxybiphenyl

Author： Verevkin S.P.

Publisher： Academic Press

ISSN： 0021-9614

Source： Journal of Chemical Thermodynamics, Vol.30, Iss.3, 1998-03, pp. : 389-396

Disclaimer: Any content in publications that violate the sovereignty, the constitution or regulations of the PRC is not accepted or approved by CNPIEC.

Previous Menu Next

Abstract

The standard (p°=0.1 MPa) molar enthalpies of formation ∆_fH_m°(cr) at the temperature T=298.15 K were measured by using combustion calorimetry of 2-phenylphenol, 4-phenylphenol, 2,6-diphenylphenol, 2,2′-dihydroxybiphenyl, and 4,4′-dihydroxybiphenyl. The standard molar enthalpies of sublimation ∆_cr^gH_m° of the compounds were obtained from the temperature variation of the vapour pressure measured in a flow system. Molar enthalpies of fusion ∆_cr¹H_m° of the compounds were measured by d.s.c. Values of the weak interactions (about 2 kJ·mol^-1 to 4 kJ·mol^-1) of phenyl substituents with the hydroxyl group were derived from the enthalpies of formation in the gas phase.∆_fH_m°(cr)kJ·mol^-1∆¹_crH_m°kJ·mol^-1∆^g_crH_m°kJ·mol^-1∆_fH_m°(g)kJ·mol^-12-phenylphenol-88.3 ± 0.615.48 ± 0.2188.54 ± 0.90.2 ± 1.14-phenylphenol-106.2 ± 0.731.59 ± 0.21109.8 ±1.03.6 ± 1.22,6-diphenylphenol14.5 ± 1.6119.1 ±1.1104.6 ± 1.92,2′-dihydroxybiphenol-293.9 ± 0.625.36 ± 0.21114.4 ± 1.2-179.5 ± 1.34,4′-dihydroxybiphenol-320.3 ± 1.643.05 ± 0.21143.0 ± 2.0-177.3 ± 2.6