Authors:E. Labarthe, A. J. Bougrine, and H. Delalu
The N -aminopiperidine, hydrazine of great interest, is often used in pharmaceutical applications. It is produced by reaction between the hydroxylamine- O -sulfonic acid and a large excess of piperidine (C 5 H 10
Two isothermal sections of the isobaric ternary system H2O–Na2SO4–C5H10NH were determined by isoplethic thermal analysis at 293 and 323 K. The compositions of the aqueous and organic invariant
liquids, respectively L1 and L2, as well as that of the critical point, were characterized for each isotherm. The temperature
of the invariant reaction was obtained by controlled flow thermal analysis and the temperature of the demixing ending, by
interpolation of the monovariant lines. All these informations allowed us to establish the isobaric polythermal diagram of
the H2O–Na2SO4–C5H10NH system, for the temperature range 293–323 K, as well as a qualitative representation of the monovariant curves. This system
is then characterized by a wide miscibility gap, three crystallization domains, and four-three-phase invariant domains. The
relevant exploitation of this diagram so permits us to deduce the demixing temperature leading to the optimal transfer of
the organic compounds in the light phase and also the composition of the organic phase recovered after this first step of
The standard (po=0.1 MPa) molar energies of combustion for the crystalline 1-benzyl-4-piperidinol and 4-piperidine-piperidine, and for the
liquid 4-benzylpiperidine, were measured by static bomb calorimetry, in oxygen, at T=298.15 K. The standard molar enthalpies of sublimation or vaporization, at T=298.15 K, of these three compounds were determined by Calvet microcalorimetry.
Those values were used to derive the standard molar enthalpies of formation, at T=298.15 K, in their condensed and gaseous phase, respectively.
The authors have measured the vapour pressure of the four binary systems, piperidine +tert-butyl methyl ether, piperidine +1,4 dioxane, piperidine + tetrahydropyrane and N-methyl piperidine +tert-butyl methyl ether. The measurements were carried out using an isoteniscope built by J. Jose , The vapour pressure, excess Gibbs free energies at 298.15, 303.15, 313.15, 323.15, 333.15 and 343.15 K, are reported for these mixtures. The excess Gibbs free energies have been fitted to the Redlich-Kister equation.
Bis-piperidine complexes of benzoylacetonates of Mn(II), Co(II), Cd(II) and Ni(II) were prepared. Thermogravimetric analysis (TG) demonstrated that Mn(II) bis-piperidine benzoylacetonate was stable up to 90°C, while Co(II) bis-piperidine benzoylacetonate was stable up to 100°C, whereas Cd(II) bis-piperidine benzoylacetonate was stable up to only 50°C. Its first decomposition step was completed at 110°C. Ni(II) bis-piperidine benzoylacetonate found to be stable up to 110°C. The stabilities of the complexes of these metals therefore follow the sequence Cd2+<Mn2+<Co2+<Ni2+. The complex of Cd(II) was the least stable of all the compounds studied.
Authors:H. Sifaoui, A. Ait-kaci, and H. Benmakhlouf
Heats of mixing HE at 303.15 K and 1 atm are reported for two ternary liquid mixtures piperidine(1)+ benzene(2)+cyclohexane(3) and piperidine(1)+benzene(2)+n -octane(3). A Redlich-Kister type smooting equation was used to represent and correlate the results.
The complexes of piperidine dithiocarbamate, 2-aminopyridine dithiocarbamate and organotin(IV) of the type R3Sn(L1), R2Sn(L1)2, R3Sn(L2), R2Sn(L2)2, [R=C6H5CH2 (benzyl), p-ClC6H4CH2 (p-chlorobenzyl), L1=sodium piperidine dithiocarbamate and L2=sodium 2-aminopyridine dithiocarbamate] have been synthesised and characterised by spectral studies (IR, UV, 1H NMR). Thermogravimetric (TG) and differential thermal analytical (DTA) studies have beeen carried out for these complexes
and from the TG curves, the order and apparent activation energy for the thermal decomposition reactions have been elucidated.
The various thermal studies have been correlated with some structural aspects of the complexes concerned. From DTA curves,
the heat of reaction has been calculated.
Authors:F. Belaribi, G. Belaribi-Boukais, A. Ait-Kaci, and J. Jose
The authors have measured the vapour pressure of four binary systems, morpholine+piperidine, morpholine+1,4-dioxane, morpholine+tetrahydropyrane
and 1,4-dioxane+tetrahydropyrane. The measurements were carried out using an isoteniscope built by J. Jose . The vapour
pressure, excess Gibbs free energies at 298.15, 303.15, 313.15, 323.15, 333.15 and 343.15 K are reported for these mixtures.
The excess Gibbs free energies have been fitted to the Redlich-Kister equation.
The authors have measured the vapour pressure of the binary four systems, piperidin +1,4-dioxan, piperidin+tetrahydropyran,
piperidin+tert-butyl methyl ether and N-methyl piperidin+tert-butyl methyl ether. The measurements were carried out using an isoteniscope built by J. Jose . The vapour pressure, excess
Gibbs free energies at 298.15 K, 303.15 K, 313.15 K, 323.15 K, 333.15 K and 343.15 K, are reported for these mixtures. The
excess Gibbs free energies have been fitted to the Redlich-Kister equation.
Authors:Zhiwei Wu, Fan Yang, Huabang Wang, Jianchao Ma, Ligong Chen, and Yang Li
-azepine, piperazine, piperidine and pyrrolidine over Cu 20 Cr 10 La 10 / γ -Al 2 O 3 . The main reactions are depicted in Scheme 1 and the results of the cyclization of aminoalcohols are described in Table 3 .