scholarly journals Mn(III)acetate-Induced Electron Transfer in Pentaammine Cobalt(III)Complexes of α-Amino Acids in Micellar Medium

2012 ◽  
Vol 9 (2) ◽  
pp. 912-917
Author(s):  
S. Udhayavani ◽  
K. Subramani
Keyword(s):  
Amino Acids ◽  
Electron Transfer ◽  
Sulphuric Acid ◽  
Carbonyl Compound ◽  
Carbonyl Compounds ◽  
Acidic Medium ◽  
Micellar Medium ◽  
Uv Visible ◽  
Experimental Findings ◽  
Catalyzed Oxidation

A micellar catalyzed oxidation of pentaamminecobalt(III) complexes of α-amino acids by Mn(III)acetate in acidic medium yielding nearly 100% Co(II) and about 100% carbonyl compounds are ultimate products. The unbound amino acids yield about 100% of carbonyl compound in presence of micelles. The effect of variation of sulphuric acid has been carried. The decrease in UV-Visible absorbance at λ=502 nm for Co(III) complex corresponds to nearly 100% of the initial absorbance. In spite of the stoichiometry of Mn(III) to unbound ligand is 2:1, the ratio of Mn(III) to cobalt(III) complex is 1:1 accounting for about 100% reduction at the cobalt(III) centre. The kinetic and stoichiometric results have been accounted. A suitable mechanism consistent with the experimental findings has been proposed by involving a radical cation intermediate.

scholarly journals Kinetic Study on Induced Electron Transfer Reaction in Pentaamminecobalt(III) Complexes of α-Hydroxy Acids by Pyridinium Fluorochromate in Micellar Medium

2011 ◽  
Vol 8 (3) ◽  
pp. 1102-1107
Author(s):  
B. Mohammed Nawaz ◽  
K. Subramani ◽  
Mansur Ahmed
Keyword(s):  
Electron Transfer ◽  
Kinetic Study ◽  
Carbonyl Compounds ◽  
Transfer Reaction ◽  
Electron Transfer Reaction ◽  
Micellar Medium ◽  
Hydroxy Acids ◽  
Uv Visible ◽  
Pyridinium Fluorochromate

Pyridinium fluorochromate (PFC) oxidation of pentaamminecobalt(III) complexes of α-hydroxy acids in micellar medium yielding nearly 100% of carbonyl compounds are ultimate products. The decrease in UV-visible absorbance at λ=502 nm for Co(III) complex corresponds to nearly 100% of the initial absorbance. The stoichiometry of unbound ligand and cobalt(III) complex is accounting for about 100% reduction at the cobalt(III) centre. The kinetic and stoichiometric results have been accounted by a suitable mechanism.

Tosyl-a-amino Acids. III. The Acid-catalysed Degradation of Tosyl-α-amino Acids and Derivatives

1963 ◽  
Vol 16 (5) ◽  
pp. 889 ◽  
Author(s):  
AF Beecham
Keyword(s):  
Amino Acids ◽  
Carbon Monoxide ◽  
Carbon Atom ◽  
Sulphuric Acid ◽  
Carbonyl Compound ◽  
Amino Acids And Derivatives ◽  
Relationship Of ◽  
The Relationship

Tosyl-α-amino acids, their chlorides and esters, evolve carbon monoxide when dissolved in concentrated sulphuric acid. Toluene-p-sulphonamide and a carbonyl compound are produced when water is added to the resulting solutions. The ease of degradation depends upon the nature of the substituents at the α-carbon atom. The relationship of these to similar degradations of substituted α-amino acids is discussed.

Ag (I) Catalyzed Oxidation of SO2 in Aqueous Solution Differing Effect of Benzoate Ions in Acidic Medium

2017 ◽  
Vol 7 (4) ◽  
Author(s):  
Arun Kumar Sharma ◽  
Pradeep Parasher ◽  
Rashmi Sharma ◽  
Davarakonda S.N. Prasad
Keyword(s):  
Aqueous Solution ◽  
Acidic Medium ◽  
Differing Effect ◽  
Catalyzed Oxidation

Racemization rates of 3,4-didehydro-2-amino acids

1989 ◽  
Vol 54 (12) ◽  
pp. 3381-3386 ◽  
Author(s):  
Libor Havlíček ◽  
Jan Hanuš ◽  
Jan Němeček
Keyword(s):  
Amino Acids ◽  
Acetic Acid ◽  
Acidic Medium

The racemization rates of amino acids in acidic medium (acetic acid) were studied. The sensitivity to racemization decreases in the order (E)-3,4-didehydroornithine > (E)-Nδ-Z-3,4-didehydroornithine >> (Z)-3,4-didehydronorvaline > ornithine, norvaline. (E)-3,4-Didehydroornithine is also relatively rapidly racemized on heating with 5 M or 0.05 M-HCl (100 °C).

scholarly journals Theoretical Analyses of Photoinduced Electron Transfer from Aromatic Amino Acids to the Excited Flavins in Some Flavoproteins

10.5772/38078 ◽  
2012 ◽  
Author(s):  
Kiattisak Lugsanangarm ◽  
Nadtanet Nunthaboot ◽  
Somsak Pianwanit ◽  
Sirirat Kokpol ◽  
Fumio Tanak
Keyword(s):  
Amino Acids ◽  
Electron Transfer ◽  
Photoinduced Electron Transfer ◽  
Aromatic Amino Acids ◽  
Theoretical Analyses

Studies on electrooxidation of lignin and lignin model compounds. Part 1: Direct electrooxidation of non-phenolic lignin model compounds

Holzforschung ◽  
2012 ◽  
Vol 66 (3) ◽  
Author(s):  
Takumi Shiraishi ◽  
Toshiyuki Takano ◽  
Hiroshi Kamitakahara ◽  
Fumiaki Nakatsubo
Keyword(s):  
Electron Transfer ◽  
Cyclic Voltammetry ◽  
Carbonyl Compounds ◽  
Model Compounds ◽  
Lignin Model Compounds ◽  
Bulk Electrolysis ◽  
Lignin Model ◽  
Dimeric Compound ◽  
High Yields ◽  
Short Time

Abstract The direct anodic oxidation of non-phenolic lignin model compounds was investigated to understand their basic behaviors. The results of cyclic voltammetry (CV) studies of monomeric model, such as 1-(4-ethoxy-3-methoxyphenyl)ethanol, are interpreted as the oxidation for Cα-carbonylation did not proceed in the reaction without a catalyst, but a base promotes this reaction. Indeed, the bulk electrolyses of the monomeric lignin model compounds with 2,6-lutidine afforded the corresponding Cα-carbonyl compounds in high yields (60–80%). It is suggested that deprotonation at Cα-H in the ECEC mechanism (E=electron transfer and C=chemical step) is important for Cα-carbonylation. In the uncatalyzed bulk electrolysis of a β-O-4 model dimeric compound, 4-ethoxy-3-methoxyphenylglycerol-β-guaiacyl ether, the corresponding Cα-carbonyl compound was not detected but as a result of Cα-Cβcleavage 4-O-ethylvanillin was found in 40% yield. In the electrolysis reaction in the presence of 2,6-lutidine (as a sterically hindered light base), the reaction stopped for a short time unexpectedly. These results indicate the different electrochemical behavior of simple monomeric model compounds and dimeric β-O-4 models. The conclusion is that direct electrooxidation is unsuitable for Cα-carbonylation of lignin.

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