Experimental and computational thermochemistry of 1-phenylpyrrole and 1-(4-methylphenyl)pyrrole

Experimental and computational energetic study of two halogenated 2-acetylpyrrole derivatives: 2-Trichloroacetylpyrrole and 2-trifluoroacetylpyrrole

“…The enthalpies of sublimation, at T = 298.15 K, D g cr H m , were derived from the same thermodynamic parameter, at the mean temperature hTi of the experiment, by equation (8) According to estimations made by other authors [44], the value of D g cr C p;m considered was À50 J Á K À1 Á mol À1 , a value that has already been used in previous works devoted to other organic compounds [9,10,12,[45][46][47][48][49][50][51][52][53]. Table 7 presents, for each compound, the values, at T = 298.15 K, of the standard molar enthalpies, entropies, and Gibbs energies of sublimation.…”

“…It has been already shown, in previous work that focused on the study of pyrrole derivatives that the G3(MP2)//B3LYP method seems to work well with this family of compounds, not only for estimating gas-phase enthalpies of formation, but also for calculating some other thermodynamic properties [9][10][11][12]. Therefore, this computational approach was also used, in this work, to compute N-H bond dissociation enthalpies (BDE), gas-phase acidities (DG acidity ) and basicities (DG basicity ), proton affinities (PA), and adiabatic ionization enthalpies (IE) for the title compounds, properties that may be difficult to measure experimentally.…”

“…In recent work we reported experimental and theoretical thermochemical studies of some pyrrole derivatives, in particular 2-and 3-acetylpyrroles [9], 2-pyrrolecarboxylic acid and 1-methyl-2-pyrrolecarboxylic acid [10], 2-and 3-acetyl-1-methylpyrroles [11], 1-phenylpyrrole and 1-(4-methylphenyl)pyrrole [12]. In this work, we have carried out the experimental determination of the standard (p ¼ 0:1 MPa) molar enthalpies of formation, in the gaseous phase, at T = 298.15 K, of two halogenated 2-acetylpyrrole derivatives: 2-trichloroacetylpyrrole and 2-trifluoroacetylpyrrole (figure 1).…”

Living on pyrrolic foundations – Advances in natural and artificial bioactive pyrrole derivatives

“…Phenylpyrrole derivatives have been demonstrated to exhibit promising biological activity and pharmacological properties, as well as to have significant therapeutic applications. In particular, their biological effects involve antispasmodic, antiviral and antioxidant activities, potentially applicable to the treatment of pathologies, in which an important role is played by the free radical oxidation [65].…”

Interplay of thermochemistry and structural chemistry, the journal (volume 24, 2013, issues 5–6) and the discipline

“…In addition, the enthalpies of formation of 1-(3,5-dichlorophenyl)pyrrole, 1-(3,5-dichlorophenyl)-2-methylpyrrole, 1-phenyl-3-pyrrolecarboxaldehyde, and 2-methyl-1-phenyl-3-pyrrolecarboxaldehyde were also calculated. The current authors previously studied a variety of other substituted 1-phenylpyrroles; accompanying the parent species [168,169] is its p-methyl [169], p-fluoro, chloro, and iodo derivatives [170]. It has long been known that 1-phenylpyrrole can be thermally isomerized to its 2-phenyl isomer [171], reflecting the fact that the 2-phenyl isomer is more stable.…”