Autor: |
Surendra G. Sudrik, Sambhaji P. Chavan, Harikisan R. Sonawane, Kunjukrishna P. Vijayamohanan, Nirmalya K. Chaki, Vilas B. Chavan, Subhash P. Chavan |
Rok vydání: |
2005 |
Předmět: |
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Zdroj: |
Chemistry (Weinheim an der Bergstrasse, Germany). 12(3) |
ISSN: |
0947-6539 |
Popis: |
In this work we report the unique electrocatalytic role of benzoic acid protected silver nanoclusters (Ag(n), mean core diameter 2.5 nm) in the Wolff rearrangement (Scheme 1) of alpha-diazoketones. More specifically, the presence of a Ag(n) (0)/Ag(n) (+) redox couple facilitates a nonclassical electron-transfer process, involving chemical reaction(s) interposed between two electron-transfer steps occurring in opposite directions. Consequently, the net electron transfer between the electron mediator (Ag(n)) and alpha-diazoketone is zero. In-situ UV-visible studies using pyridine as a nucleophilic probe indicate the participation of alpha-ketocarbene/ketene as important reaction intermediates. Controlled potential coulometry of alpha-diazoketones using Ag(n) as the anode results in the formation of Wolff rearranged carboxylic acids in excellent yield, without sacrificing the electrocatalyst. |
Databáze: |
OpenAIRE |
Externí odkaz: |
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