Aliphatic hydrocarbons of the Murchison meteorite.
Aliphatic hydrocarbons of the Murchison meteorite.
复制标题
默奇森陨石的脂肪族碳氢化合物。
DOI：
10.1016/0016-7037(90)90020-l
复制
发表时间：
1990
影响因子：
5
通讯作者：
S. Pizzarello
中科院分区：
文献类型：
--
作者：
J. Cronin;S. Pizzarello
由于陆地污染引起的问题，碳质球粒陨石的本土有机化合物很难确定。墨奇森陨石(CM2)的坠落提供了原始的样品，这使得先前的一些模糊的问题得以解决，例如，在氨基酸的情况下。然而，脂肪族碳氢化合物的性质仍不清楚。墨尔奇森号坠落后不久，一个实验室发现它们主要是环烷烃；另一个实验室按丰度顺序发现支链烷烃、烯烃和环烷烃；第三个实验室报告的主要是正构烷烃，其次是甲基烷烃和烯烃。我们用苯-甲醇作为萃取剂，用硅胶层析法分离萃取物，用GC-MS、IR和核磁共振光谱技术进行分析，重新研究了这个问题。当获得内部样品并在将环境污染降至最低的条件下进行分析时，我们发现Murchison陨石的主要脂肪族组分是一套结构多样化的C15至C30支链烷基取代的单环、双环和三环烷烃。对Murray(CM2)、Allende(CV3)和New Concord(L6)球粒陨石进行了对比分析，说明了碳质球粒陨石所遇到的污染问题的性质。
The indigenous organic compounds of carbonaceous chondrites have been difficult to characterize because of problems arising from terrestrial contamination. The fall of the Murchison meteorite (CM2) provided pristine samples which allowed the resolution of some prior ambiguities as, for example, in the case of the amino acids. However, the nature of the aliphatic hydrocarbons has remained unclear. Shortly after the Murchison fall, one laboratory found them to be mainly cycloalkanes; another found, in order of abundance, branched alkanes, olefins, and cycloalkanes; while a third reported predominantlyn-alkanes followed by methyl alkanes and olefins. We have reinvestigated this question using benzene-methanol as the extraction solvent, silica-gel chromatography for fractionation of the extract, and GC-MS, and IR and NMR spectroscopic techniques for the analyses. When interior samples were obtained and the analyses carried out under conditions that minimized environmental contaminants, we have found the principal aliphatic components of the Murchison meteorite to be a structurally diverse suite of C15to C30branched alkyl-substituted mono-, di-, and tricyclic alkanes. Comparative analyses were carried out on the Murray (CM2), Allende (CV3), and New Concord (L6) chondrites that illustrate the nature of the contamination problem encountered with carbonaceous chondrites.