Abstract: The invention provides a composition of matter selected from the group consisting of ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are selected from the group consisting of hydrogen and alkyl substituent groups having from 1 to about 8 carbon atoms, n is from 2 to about 20, m is from 2 to about 20, and Di is a substituted or unsubstituted diamondoid compound. The invention further provides diamondoid-containing ammonium salts, and a pharmaceutical treatment method using the compositions of the invention.

Abstract: The present invention provides a method for arylating a diamondoid compound having at least one unsubstituted bridgehead carbon with an aromatic compound having at least one unsubstituted ring-member carbon comprising reacting said diamondoid compound with said aromatic compound in the presence of an olefin and a catalytically effective amount of a Lewis acid.

Abstract: This invention provides a method for incorporating a diamondoid compound into a lubricant stock comprising reacting at least one .alpha.-olefin containing at least six carbon atoms with at least one diamondoid compound in the presence of an acid catalyst selected from the group consisting of AlX.sub.3, BX.sub.3, and GaX.sub.3, wherein X is a halogen, together with at least one added proton-donating catalyst promoter.The invention further provides a lubricant composition comprising alkyl-substituted diamondoids wherein the ratio of linear to branched alkyl substituents is at least about 4:1 and wherein the average number of alkyl substitutions per diamondoid molecule is from about 1.5 to about 4.

Abstract: The invention provides a method for selectively alkylating a diamondoid compound comprising reacting at least one .alpha.-olefin containing at least six carbon atoms with at least one diamondoid compound in the presence of an acid catalyst selected from the group consisting of AlX.sub.3 and BX.sub.3 wherein X is a halogen, in the absence of added proton-donating catalyst promoter. The invention further provides a lubricant composition comprising alkyl-substituted adamantanes wherein the ratio of linear to branched alkyl substituents is at least about 4:1 and wherein the average number of alkyl substitutions per diamondoid molecule is from about 1.5 to about 4.

Abstract: A fuel additive having detergency, solubility and thermal stability comprises a detergent component, e.g., polyalkenyl succinimide, and a carrier fluid obtained from a diamondoid fluid comprising an compound selected from the group consisting of adamantane, diamantane, triamantane, tetramantane, and the alkyl-substituted derivatives thereof.

Abstract: The invention provides a composition comprising at least about 10 different diamondoid compounds selected from the group consisting of methyl-substituted and ethyl-substituted adamantane, diamantane, and triamantane, wherein each of said selected diamondoid compounds comprises no more than about 10 weight percent of said composition. The composition is useful as high quality lubricating fluid and exhibits the unusual combination of high Viscosity Index and very low pour point.

Abstract: The invention provides a method for converting a lactone of a diamondoid compound to the hydroxyketone of the diamondoid compound wherein the hydroxyl group and the carbonyl group are separated by at least one bridgehead carbon comprising reacting an anhydride containing from about 2 to about 20 carbon atoms with the lactone of the diamondoid compound in the presence of acid.

Abstract: The invention provides a method for selectively hydroxylating a diamondoid compound to an alcohol of the diamondoid compound comprising contacting the diamondoid compound with an oxygen-containing gas under hydroxylation conditions including temperature of at least about 70.degree. C.