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J Polesuk

Publications and source records attributed to J Polesuk.

9 recordsLinked to original sources
PubMed1975

Practical kinetics I: Quantitation of barbiturate stability by TLC.

The purpose of this work was the application of established techniques to the quantitation of stability investigations of liquid formulations as well as in solution kinetic studies. The process consists of streaking aliquots of reaction solution on TLC plates, development, elution, and analysis of the substances in the eluate. Several barbiturates were investigated regarding their decomposition at elevated temperatures. Reasonable correlation is noted between obtained rate constants and literature data. This technique represents a utilitarian approach to stability screening of compounds in solution, aqueous or otherwise, where chromatographic separation and analytical methodology for the pure compound are available.

Amobarbital↗
PubMed1975

Alcoholysis of medicinally active 5-aminodibenzo(a,d)cycloheptenes.

The rate constants for alcoholic solvolysis of the hydrochloride salts of diethylaminodibenzo(a,d)cycloheptene and related amino congeners were determined. The objective was a study of the comparative ease of cleavage of the C-N amino linkage by various aliphatic alcohols. The interaction of protonated amines of this series with alcoholic hydroxyls presumably leads to formation of the corresponding ethers in a manner somewhat analogous to alkoxide reaction with alkyl bromides. The methyl ether produced from solvolysis of diethylaminodibenzocycloheptene hydrochloride was isolated and identified. Methanol appears to react somewhat more rapidly with the amine hydrochlorides than other aliphatic alcohols. The latter produce almost invariant velocity constants with a given amine hydrochloride. The exception was tertbutanol, which resulted in Kobs values about one-third of those given by the other alcohols. Some velocity constants in formic and acetic acids were evaluated. Generation of carbonium ions of appreciable lifetime was indicated in formic acid by the formation of a highly colored (red-violet) solution. This color may be a manifestation of the dibenzotropylium ion.

Acetates↗