Combined experimental and computational thermochemistry of isomers of chloronitroanilines

Experimental thermochemical study of 2,5- and 2,6-dichloro-4-nitroanilines

“…The present work is a contribution to the thermochemical investigation of halogenated anilines and nitroanilines carried out by the Molecular Energetics Research Group of the University of Porto, following the studies of fluoroanilines [6,7], chloroanilines [8][9][10][11], bromoanilines [12], iodoanilines [13] and monochloronitroanilines [14,15]. This paper reports the standard (p°= 0.1 MPa) molar enthalpies of formation, of 2,5-and 2,6-dichloro-4-nitroanilines, in the crystalline phase, at T = 298.15 K, derived from the standard massic energies of combustion, of those two compounds, in oxygen, at the same temperature, measured by rotating-bomb combustion calorimetry.…”

Experimental thermochemical study of 4,5-dichloro-2-nitroaniline

“…The present work is a contribution to the thermochemical investigation of halogenated anilines and nitroanilines carried out by the Molecular Energetics Research Group of the University of Porto, from which the fluoroanilines [3,4], chloroanilines [5][6][7][8], bromoanilines [9], iodoanilines [10], monochloronitroanilines [11,12], and two dichloro-4-nitroaniline isomers [13] have already been studied. This paper reports the standard ðp ¼ 0:1 MPaÞ molar enthalpy of formation, of 4,5-dichloro-2-nitroaniline, in the crystalline phase, at T = 298.15 K, derived from the standard massic energy of combustion, in oxygen, at the same temperature, measured by rotating-bomb combustion calorimetry.…”

Experimental and computational thermochemical study of the dichloronitrobenzene isomers

“…The calculation of frequencies also permitted us to correct energies for T = 298.15 K, by introduction of the vibrational, translational, rotational and the pV terms. The present computational procedure was chosen since in previous work devoted to the thermochemistry of chloronitroaniline isomers [18,22] permitted the estimation of accurate gas-phase enthalpies of formation. All the calculations were performed by means of the Gaussian 03 software package [59].…”

“…The choice of these molecules is due to the fact that the effects of the introduction of chlorine atoms in benzene rings [15,[17][18][19][20][21][22][23] as well as the effect of the same substituents into heterocycles [24][25][26][27][28][29][30] has been, for some years, one of the research objectives of our Research Group on thermochemical properties. The experimental investigation includes the determination of the standard molar energies of combustion, in oxygen, at T = 298.15 K, of four dichloronitrobenzene isomers, using a rotating bomb combustion calorimeter, from which the values of the standard molar enthalpies of formation, in the condensed phase, were derived.…”