Determination of thiosemicarbazide alone and in its metal complexes with arylhalosulfonamides

Gowda, B.T.; Mahadevappa, D. S.

doi:10.1016/0026-265x(83)90075-9

Microchemical Journal

1983

DOI: 10.1016/0026-265x(83)90075-9

|View full text |Cite

Determination of thiosemicarbazide alone and in its metal complexes with arylhalosulfonamides

B.T. Gowda

D. S. Mahadevappa

Help me understand this report

Search citation statements

Order By: Relevance

Paper Sections

Select...

Citation Types

Supporting

Mentioning

Contrasting

Year Published

1987

2010

Publication Types

Select...

Article4

Relationship

Self Cite0

Independent4

Authors

Journals

Cited by 4 publications

References 29 publications

(30 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

Mechanism of oxidations in partially aqueous media: Kinetics of oxidation of thiosemicarbazide and thiosemicarbazone by chloramine‐T and dichloramine‐T in aqueous methanol

Gowda

Sherigara

1989

Int J of Chemical Kinetics

View full text Add to dashboard Cite

Kinetics of oxidation of thiosemicarbazide (TSC) and its hydrazone (Benzaldehyde thiosemicarbazone) by chloramine-T (CAT) and dichloramine-T (DCT) in aqueous methanol medium in the presence of perchloric acid has been studied. Oxidation of TSC by both the oxidants showed first order dependences in [oxidant], fractional order in [TSC] and nearly inverse first order in [H']. The conversion of TSC into its benzaldehyde hydrazone changed the rate dependence in [CAT] from first to second order, while the dependence in [DCT] remained unchanged. The dependence in [TSCI changes from fractional order to zero order in both CAT and DCT oxidations. The rate followed inverse fractional order kinetics in [H'] in both the cases. Increase in ionic strength of the medium slightly decreased the rate, while the decrease in dielectric constant of the medium increased the rates of oxidations for both the oxidants. But the addition of reaction products, p-toluenesulphonamide and chloride had no effect on the rate. Oxidation of TSC with both the oxidants has been shown to follow Michaelis-Menten type mechanism. In hydrazone oxidations oxidants have been shown to disproportionate in slow steps to HOCl, which in turn attacks the substrate in fast steps to give the final products.[TSC] was varied at different temperatures and the constants of rate limiting steps were calculated at each temperature. Using the latter constants the activation parameters have been computed from the Arrhenius plots. The rate constants have been predicted from the rate law for the variation of [H'l at constant [TSCI and [oxidantl. The predicted values are in reasonable agreement with the experimental rate constants, providing additional support to the suggested mechanisms.

show abstract

Mechanism of oxidations in partially aqueous media: Kinetics of oxidation of thiosemicarbazide and thiosemicarbazone by chloramine‐T and dichloramine‐T in aqueous methanol

Gowda

Sherigara

1989

Int J of Chemical Kinetics

View full text Add to dashboard Cite

show abstract

Kinetics of oxidation of acidic amino acids and their monoamides by N‐chloroarylsulphonamides in aqueous acidic medium

Gowda¹,

Shetty²

2004

J of Physical Organic Chem

View full text Add to dashboard Cite

Twelve sodium salts of N‐chloroarylsulphonamides were employed as oxidants for studying the kinetics of oxidation of two acidic amino acids (aspartic and glutamic acid) and their monoamides (aspargine and glutamine) in aqueous acidic medium under various conditions, to see how the oxidative strength of these reagents vary with substitution. The sodium salts of N‐chloroarylsulphonamides employed are of the general formulae i‐X‐C6H4SO2NaNCl·xH2O (where i‐X = 4‐C2H5, 4‐F, 4‐Cl or 4‐Br) and i‐X‐j‐Y‐C6H3SO2NaNCl·xH2O [where i‐X‐j‐Y = 2,3‐(CH3)2, 2,4‐(CH3)2, 2,5‐(CH3)2, 2‐CH3‐4‐Cl, 2,4‐Cl2 and 3,4‐Cl2]. The reactions show second‐order kinetics in [oxidant], fractional order in [amino acid] and an inverse dependence on [H+]. Addition of the reduced product of the oxidants or variation in ionic strength of the medium has no significant effect on the rates of oxidations. Mechanisms in conformity with the observed kinetics are discussed. The effective oxidizing species of the oxidants is Cl+ in different forms. The oxidizing strengths of N‐chloroarylsulphonamides depend on the ease with which Cl+ is released from them. The study reveals that the introduction of electron‐withdrawing groups such as halides to the benzene ring eases the release of Cl+ from the reagent and hence increases the oxidizing strengths of the N‐chloroarylsulphonamides. The effect of substituents on Ea of the reactions was analysed by optimising Ea with reference to log A, and log A with reference to Ea of the parent oxidant. Copyright © 2004 John Wiley & Sons, Ltd.

show abstract

Mechanistic investigations with positive halogens; kinetics of oxidation of thiosemicarbazide by chloramine-B, bromamine-B and dichloramine-B in acid medium.

Gowda

Bhat

1987

Tetrahedron

View full text Add to dashboard Cite

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

customersupport@researchsolutions.com

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Determination of thiosemicarbazide alone and in its metal complexes with arylhalosulfonamides

Cited by 4 publications

References 29 publications

Mechanism of oxidations in partially aqueous media: Kinetics of oxidation of thiosemicarbazide and thiosemicarbazone by chloramine‐T and dichloramine‐T in aqueous methanol

Mechanism of oxidations in partially aqueous media: Kinetics of oxidation of thiosemicarbazide and thiosemicarbazone by chloramine‐T and dichloramine‐T in aqueous methanol

Kinetics of oxidation of acidic amino acids and their monoamides by N‐chloroarylsulphonamides in aqueous acidic medium

Mechanistic investigations with positive halogens; kinetics of oxidation of thiosemicarbazide by chloramine-B, bromamine-B and dichloramine-B in acid medium.

Contact Info

Product

Resources

About