Ruthenium (III)-catalyzed oxidative cleavage of phenylpropanolamine with N-bromosuccinimide in hydrochloric acid medium: a kinetic and mechanistic approach

Mohana, K. N.; Ramya, K.; Bhandarkar, P. M. Ramdas

doi:10.1007/s11144-010-0199-6

Cited by 2 publications

(4 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similar studies were undertaken for the oxidation of allyl alcohol, − benzyl ethers, benzhydrols, amines and amino alcohols, − glycols, , cardiotoxin II,nitrones and N ,α-diphenylnitrones, , dibenzyl sulfoxide, and substituted aromatic acetals . Oxidative cleavage of thiamine hydrochlorideand phenylpropanolamine and oxidative conversion of glutathione to glutathione disulfide, were also studied in a similar context. During the study of the oxidation of azides with NBS, it was observed that the rate of oxidation of N 3 – in an aqueous medium is proportional to [N 3 – ] and [NBS] at constant [Hg(OAc) 2 ] .…”

Section: Oxidation Reactionsmentioning

confidence: 99%

Use of Bromine and Bromo-Organic Compounds in Organic Synthesis

2016

View full text Add to dashboard Cite

Bromination is one of the most important transformations in organic synthesis and can be carried out using bromine and many other bromo compounds. Use of molecular bromine in organic synthesis is well-known. However, due to the hazardous nature of bromine, enormous growth has been witnessed in the past several decades for the development of solid bromine carriers. This review outlines the use of bromine and different bromo-organic compounds in organic synthesis. The applications of bromine, a total of 107 bromo-organic compounds, 11 other brominating agents, and a few natural bromine sources were incorporated. The scope of these reagents for various organic transformations such as bromination, cohalogenation, oxidation, cyclization, ring-opening reactions, substitution, rearrangement, hydrolysis, catalysis, etc. has been described briefly to highlight important aspects of the bromo-organic compounds in organic synthesis.

show abstract

Section: Oxidation Reactionsmentioning

confidence: 99%

Use of Bromine and Bromo-Organic Compounds in Organic Synthesis

2016

View full text Add to dashboard Cite

show abstract

“…Focusing on A and B as the major degradation products, we need to understand how our starting material breaks down at low pH. It was reported that the reaction of phenylpropanolamine with N -bromosuccinimide (as an oxidizing agent) in the presence of a HCl solution yielded benzaldehyde ammonia and acetaldehyde . A similar mechanism can be written for CpQ degradation at low pH.…”

Section: Resultsmentioning

confidence: 99%

“…It was reported that the reaction of phenylpropanolamine with N-bromosuccinimide (as an oxidizing agent) in the presence of a HCl solution yielded benzaldehyde ammonia and acetaldehyde. 10 A similar mechanism can be written for CpQ degradation at low pH. The reaction occurs by a polar mechanism under acidic conditions.…”

Section: ■ Materials and Methodsmentioning

confidence: 96%

“…Considering the low-pH isomerization, there are literature reports of chiral interconversion of structurally similar compounds, such as L-adrenaline, in which isomerization occurs by a polar mechanism under acidic conditions through carbocation stabilization of the chiral center by the aromatic ring. 10 Similarly, CpQ can be converted from the R to S isomer via a carbocation intermediate, stabilized by the aromatic ring. The proposed mechanism of isomerization is shown in Scheme 2.…”

Section: ■ Materials and Methodsmentioning

confidence: 99%

See 1 more Smart Citation

Kinetics and Degradation Mechanism of Adrenaline Derivative CpQ in Diluted Aqueous Solutions

et al. 2018

View full text Add to dashboard Cite

The degradation kinetics of an adrenaline (epinephrine) derivative, CpQ, was studied in solution in the pH range of 1-12 at 40-80 °C by high-performance liquid chromatography and ultraviolet-visible spectroscopy. The pH-rate profile exhibits a bell-shaped curve with two sigmoidal regions in the specific acid-catalyzed and specific base-catalyzed regions. The pH range of maximum stability was 2.5-4.5 with the main degradation pathway being the oxidative N-dealkylation of the aliphatic amino moiety followed by fast interconversion of the resulting fragments to stable degradation products. The autoxidation reaction was slower than the reaction of the oxygen reactive species. The chiral center underwent R to S racemization by a polar reaction mechanism under acidic conditions with a rate minimum at pH 4. The rates of degradation of the R and S enantiomers were similar across all pHs. CpQ degradation in the presence of hydrogen peroxide at 40 °C was significantly faster, and the extent of increases with pH. Metal ions bind to CpQ and catalyze its hydrolysis in the order Fe > Fe > Mg > Mn > Ti > Sr > Zn, with a rate enhancement of ≤1 order of magnitude at the studied pH values of 1 and 5. There was no buffer catalysis observed in the hydrolysis of the studied compound for maleate and phosphate but significant buffer catalysis in the case of citrate and malate.

show abstract

Ruthenium (III)-catalyzed oxidative cleavage of phenylpropanolamine with N-bromosuccinimide in hydrochloric acid medium: a kinetic and mechanistic approach

Cited by 2 publications

References 24 publications

Use of Bromine and Bromo-Organic Compounds in Organic Synthesis

Use of Bromine and Bromo-Organic Compounds in Organic Synthesis

Kinetics and Degradation Mechanism of Adrenaline Derivative CpQ in Diluted Aqueous Solutions

Contact Info

Product

Resources

About