Abstrakt
In the Bilina Mine (Czech Republic), a very chemically pure material corresponding to hartite was found as a product of distillation into the pelosiderite nodule during coalification of a lignite seam in the Miocene or later. The amount of the material available allowed characterizing this natural mineral equivalent of the hydrocarbon (+)-phyllocladane [16 alpha(H)-phyllocladane] thoroughly.
Elementary analysis of hartite from Bilina gave C = 87.45 wt% and H = 12.55 wt%, which corresponds to the formula C20H34. The IR spectrum demonstrated the presence of gem-dimethyl groups (doublet delta(5)CH(3) at 1369 and 138 3 cm(-1)). Other bands indicated the presence of methyl and methylene groups. NMR studies showed that the hydrocarbon (hartite) molecule contains four CH3 groups, nine CH2 groups, four CH groups, and three quaternary carbon atoms. The sample exhibits a well-defined melting point between 71 and 71.5 degrees C. Measurements of optical rotation gave [alpha](D) = +24.2 degrees (CHCl3, c = 0.7). Lattice parameters from single-crystal study measured at 293(2) K were a = 11.407 (1), b = 20.952 (2), c = 7.4060 (8) Angstrom, alpha = 93.941 (9)degrees, beta = 100.750 (8)degrees, and gamma = 80.499 (9)degrees. The crystal system is triclinic with space group P1, Z = 4, V = 1713.8 (3) Angstrom(3). Densities are D-m = 1.04 g/cm(3) and D-x = 1.064 g/cm(3), respectively. Isotopic composition of C in hartite from Bilina gave delta(13)C((PDB)) = -24.4(1) parts per thousand, a common value for coal and organic sedimentary material derived from higher plants.