Title : Synthetic and analytical applications of chloramine-T
Abstract:
Chloramine-T in the hydrate form has been used in various types of chemical reactions. This prompted us to utilize chloramine-T as mild oxidant for oxidizing alcohol to aldehydes. Allylic amination of β-apopicropodophyllin and epoxidation of podophyllotoxone were successfully achieved by chloramine-T in presence of selenium/copper catalyst and dimethyl sulphoxide respectively. Generation and isolation of unstable intermediates such as nitrile oxide and nitrile imenes were achieved for the first time by the reaction of aldoximes and phenyl hydrazones respectively with chloramine-T in ethanol as solvent, which later underwent 1,3-dipolar cyloaddition reaction with alkenes to form the corresponding heerocycles. Similarly we have used chloramine-T for the [4+2]-cycloaddition of α-nitrosoolefins and azoalkenes with alkenes starting from ketooximes and ketohydrazones respectively in almost quantitative yield. The synthesized products such as isoxazolines, isoxazoles, pyrazolines, pyrazoles, 1,3,4-oxadiazole, 1,2-oxazine, 1,2-diazine derivatives were screened for various biological activity and liquid crystalline properties.
Besides the synthetic application of chloramine-T, we have successfully utilized this simple reagent for the determination of iodine value of an oils, number of keto group in many carbonyl compounds, keto-enol contents in β-keto dicarbonyl compounds and molecular weight of oximes, neutral amino acids, ascorbic acid iodometrically. Some of the methods were successfully adopted in M. Sc., and B. Sc., practical classes in few Indian universities.
