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The isobaric melting and boiling diagrams for the systems: pyridine/methyltrichlorosilane and pyridine/1,1,1-trichloroethane are reproduced. The existence of the congruently melting addition compound CH3SiCl3· (Pyridin)2 could be confirmed. Some measurements of the molar volume of mixtures between pyridine and methyltrichlorosilane and pyridine and 1,1,1-trichloroethane, respectively, are reported. For both systems the molar excess volume and for the system pyridine/methyltrichlorosilane the molar excess enthalpie have been calculated as a function of the mole fractions.
The isobaric melting and boiling diagrams for the systems: dimethyldichlorosilane/pyridine and 2,2-dichloropropane/pyridine are reproduced. The existence of the incongruently melting addition compounds (CH3)2SiCl2 · (Pyridine)2 and [(CH3)2CCl2]3 · Pyridine could be proved. Some measurements of the molar volume of mixtures of pyridine and dimethyldichlorosilane, and pyridine and 2,2-dichloropropane are reported. For both systems the molar excess volume has been calculated as a function of the mole fractions.
The isobaric melting and boiling diagrams for the systems: trimethylchlorosilane/pyridine and trimethylchloromethane/pyridine are reproduced. Some measurements of the molar volume of mixtures between trimethylchlorosilane and pyridine and trimethylchloromethane and pyridine are reported. For both systems the molar excess volume has been calculated as a function of the mole fractions
A phase equilibrium study of the system aluminiumbromide and pyridiniumbromide has been carried out. The phase diagram of the system indicates the existence of three congruently melting com pounds of the molar ratio AlBr3/PyHBr 1:1, 1:3, 2 :3 and one incongruently melting compound of the molar ratio 1:2 and is therefore similar to the AlCl3-PyHCl system [1].
A phase equilibrium study of the system aluminiumchloride and pyridiniumchloride has been carried out. The phase diagram of the system indicates the existence of four congruently melting compounds of the molar ratio AlCl3/PyHCl 1:1, 1:2, 1:3, 2:3.
Phase equilibrium studies of the Lewis acid-base systems AlCl3/PyHBr and AlBr3/PyHI indicate the existence of congruently melting compounds of the molar ratios 1:1 and 2:3.
These results are quite different from those of our studies of the AlCl3/PyHCl and the AlBr3/PyHBr systems, in which four compounds in the molar ratios 1:1, 1:2, 1:3, and 2:3 could be detected.
The melting point of pyridinium iodide observed at 284,8 °C (decomp.) differs from the previously reported one.
Crystals of [Al(C5H5N)4Cl2][AlCl4] are orthorhombic, Pna21, Z = 4, a = 18.522(7), b = 15.141(5), c = 9.593(3) Å, V = 2690(2) Å3 , Dc = 1.440 g/cm3 . The structure has been solved from 5968 diffractometer measured intensities and refined by full-matrix least squares to Rw(F) = 0.032. The crystal structure shows the complex to be trans-dichloro-tetrakis(pyridine)aluminium(III) tetrachloroaluminat(III). The mean trans Al-Cl-and trans Al-N-distances in the octahedron are 2.279(3) and 2.070(4) Å, respectively. Crystals of Al(C5H5N)3Cl3 are monoclinic, P21/c, Z = 4, a = 7.261(2), b = 29.961(4), c = 8.624(1) Å, β = 98.12(2)°, V -1857(1) Å3 , DC = 1.326 g/cm3 . The structure has been solved from 4707 diffractometer measured intensities and refined to Rw(F) = 0.028. The crystal structure shows octahedral complexes AlCl3·3 (C5H5N) with trans geometry. The Al-N-distance trans to chlorine (2.096(2) Å) is significantly longer than the two other Al-N-distances (mean 2.072(2) Å).
The phase diagrams of the systems of trimethylbromosilane and the isomeric lutidines are shown. The existence of the congruently melting addition compounds (CH3)3SiBr ∙ (3,4-lutidine), (CH3)3SiBr (3,5-lutidine) and the incongruently melting addition compounds (CH3)3SiBr • (2,3-lutidine)2, (CH3)3SiBr • (2,3-lutidine), (CH3)3SiBr (2,4-lutidine), ((CH3)3SiBr)2 • (2,4-lutidine), (CH3)3SiBr • (2,5-lutidine)2, (CH3)3SiBr • (2,5-lutidine), (CH3)3SiBr (2,6-lutidine)2 could be proved.
Trimethylbromosilane and 3,4-lutidine form a 1:1 compound which is stable at room temperature. Single crystals of this compound can be isolated by sublimation. It crystallizes in the orthorhombic space group P 2121,21, with lattice constants a = 737,08(9) pm, b = 1295,7(1) pm, c = 1318,8(3) pm. The crystal structure was refined to Rw = 0,042 and proves an ionic structure.
By analyzing the DSC heating curves and the resulting phase diagrams of the systems of dibromodimethylsilane and 2-, 3- or 4-methylpyridine the existence of the congruently melting addition compounds ((CH3)2SiBr2)2 · (3-methylpyridine) and (CH3)2SiBr2 · (4-methylpyridine)2, and the incongruently melting addition compounds ((CH3)2SiBr2)2 · (2-methylpyridine) and ((CH3)2SiBr2)2 · (4-methylpyridine) could be proved.