The nitrogen compounds of petroleum?IV. Group separation of concentrates of nitrogen bases

Crude Petroleum

“…The discovery of 2-(2,2,6-trimethylcyclohexyl)-4,6-dimethylpyridine [148J and very recently of the optically active 2,4,7a,8,8-pentamethylcyclopenta(f)pyrindan [149J lend considerable support to the correlation of petroleum nitrogen compounds with naturally occurring alkaloids [150]. Other basic nitrogen types reported in petroleum are ct-hydroxybenzo-and benzoquinolines, indoloquinolines, phenanthrolines and tetrahydrocarbazole nines [151J, although the presence of some of these compounds is in dispute [152J, acridines and dihydroacridines are reported in [147J Russian crude oils [153].…”

Effect of Electrophilic and Electrodotic Groups on the Titration of Amides and Other Weak Bases

“…Acetic anhydride has been used alone as a titration medium or in combination with other solvents (2)(3)(4)(5)(6)(7)(8)(9)(10). A good summary has been presented by Wimer (1).…”