ICOSAHEDRAL CARBORANES. XIII. HALOGENATION OF P-CARBORANE

• Main Authors: Sieckhaus,John F, Semenuk,Nick S, Knowles,Thomas A, Schroeder,Hansjuergen
• Format: Report
• Language: English
• Subjects: BORANES; BROMINE COMPOUNDS; CHLORINE COMPOUNDS; CHROMATOGRAPHIC ANALYSIS; ELECTROCHEMISTRY; HALOGENATION; Inorganic Chemistry; IODINE COMPOUNDS; MOLECULAR ISOMERISM; PHOTOCHEMICAL REACTIONS; PURIFICATION; STEREOCHEMISTRY; SYNTHESIS(CHEMISTRY)

A method for the preparation and purification of substantial amounts of p-carborane is described. Chloro-, bromo- and iodo-p-carboranes were obtained via direct halogenation. The various halogenated species were separated by either column or vapor phase chromatography. In the chloro-p-carborane series, the mono-, nona- and decachlorinated compounds are individual species; the others occur as mixtures of geometrical isomers. Separation of the latter was accomplished by high resolution VPC using capillary column techniques. Interpretation of the chromatograms of these chlorinated derivatives proved consistent with the formation of all possible isomeric species in approximately those quantities which would be predicted on a statistical basis. None of these isomers was physically isolated, however. In contrast, partial fractionation of the dibromo- and diiodo-p-carborane isomer mixtures proved possible by common laboratory techniques. (Author)