The Determination of the Bridge Structure of Dipyrrylmethanes. A New Method for the Estimation of Active Hydrogen¹

Abstract

The preceding paper of this series3 showed that the imide hydrogens of certain dipyrrylmethanes do not react with molten sodium and potassium.Conceivably, these peculiarities could be due to

Titration of Pharmaceuticals in Nonaqueous Solvents *

“…The acidic carboxyl group may be titrated as described above. These compounds are very weakly acidic and have been titrated with sodium triphenylmethane (9), which serves as its own indicator.…”

Titration of organic compounds as very weak acids with lithium [1,1,1-trimethyl-N-(trimethylsilyl)]silanamide

“…Analytical methods for the determination of nitrogenous organic compounds often require time-consuming processes as in the determination of amines and ureas (1). More convenient procedures are direct titrations of these compounds in nonaqueous solvents by the use of sufficiently soluble titrants such as sodium dimethylsulfoxide (2), lithium aluminum hydride (3), lithium aluminum amides (4), tetrabutylammonium hydroxide (5,6), and sodium amide (7). More recently, lithium diisopropylamide in tetrahydrofuran (THF) was employed for the titration of several carbamates (8).…”