Study of the stability of the phenanthrene- and 1,2-benzanthracene-choleic acids by vapor pressure measurements

The stablllty of the phenanthrene- and 1,2-benzanthracene-cholelc aclds (DCAPHE and DCABAN, rerpectlvety) was studied by meaufrlng thelr vapor pressure by means of the tordon-ethdon method. The temperature dependence of the gaseous guests over thelr channel complexes was determined: DCAPHE, logP(kPa) = (13.09 f 0.50) - (674300)/T; DCABAN, log P(kPa) = (12.46 f 0.70) - (6600 f 400)/r. From the second-law vaporlzatlon enthalpy change, the enthalpy of the reaction 3DCA(s) + X(g) - (DCA),X(s) was derhred, where DCA and X represent deoxycholic acid and aromatlc hydrocarbon, respectively. The rewlts are compared wlth thore obtdned prevlourly for dmllar choleic acMI contalnlng styrene and naphthalene.