Silver Nanocluster Redox-Couple-Promoted Nonclassical Electron Transfer: An Efficient Electrochemical Wolff Rearrangement of α-Diazoketones
Surendra G. Sudrik Dr.
Division of Organic Chemistry: Technology, National Chemical Laboratory, Pune 411 008, India, Fax: (+91) 20-2589-3614
Search for more papers by this authorNirmalya K. Chaki
Physical and Materials Chemistry, National Chemical Laboratory, Pune 411 008, India, Fax: (+91) 20-2589-3044
Search for more papers by this authorVilas B. Chavan Dr.
Division of Chemical Engineering and Process Development, National Chemical Laboratory, Pune 411 008, India
Search for more papers by this authorSambhaji P. Chavan
Division of Organic Chemistry: Technology, National Chemical Laboratory, Pune 411 008, India, Fax: (+91) 20-2589-3614
Search for more papers by this authorSubhash P. Chavan Dr.
Division of Organic Chemistry: Technology, National Chemical Laboratory, Pune 411 008, India, Fax: (+91) 20-2589-3614
Search for more papers by this authorHarikisan R. Sonawane Dr.
Division of Organic Chemistry: Technology, National Chemical Laboratory, Pune 411 008, India, Fax: (+91) 20-2589-3614
Search for more papers by this authorK. Vijayamohanan Dr.
Physical and Materials Chemistry, National Chemical Laboratory, Pune 411 008, India, Fax: (+91) 20-2589-3044
Search for more papers by this authorSurendra G. Sudrik Dr.
Division of Organic Chemistry: Technology, National Chemical Laboratory, Pune 411 008, India, Fax: (+91) 20-2589-3614
Search for more papers by this authorNirmalya K. Chaki
Physical and Materials Chemistry, National Chemical Laboratory, Pune 411 008, India, Fax: (+91) 20-2589-3044
Search for more papers by this authorVilas B. Chavan Dr.
Division of Chemical Engineering and Process Development, National Chemical Laboratory, Pune 411 008, India
Search for more papers by this authorSambhaji P. Chavan
Division of Organic Chemistry: Technology, National Chemical Laboratory, Pune 411 008, India, Fax: (+91) 20-2589-3614
Search for more papers by this authorSubhash P. Chavan Dr.
Division of Organic Chemistry: Technology, National Chemical Laboratory, Pune 411 008, India, Fax: (+91) 20-2589-3614
Search for more papers by this authorHarikisan R. Sonawane Dr.
Division of Organic Chemistry: Technology, National Chemical Laboratory, Pune 411 008, India, Fax: (+91) 20-2589-3614
Search for more papers by this authorK. Vijayamohanan Dr.
Physical and Materials Chemistry, National Chemical Laboratory, Pune 411 008, India, Fax: (+91) 20-2589-3044
Search for more papers by this authorGraphical Abstract
Abstract
In this work we report the unique electrocatalytic role of benzoic acid protected silver nanoclusters (Agn, mean core diameter 2.5 nm) in the Wolff rearrangement (Scheme 1) of α-diazoketones. More specifically, the presence of a Agn0/Agn+ 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 (Agn) and α-diazoketone is zero. In-situ UV-visible studies using pyridine as a nucleophilic probe indicate the participation of α-ketocarbene/ketene as important reaction intermediates. Controlled potential coulometry of α-diazoketones using Agn as the anode results in the formation of Wolff rearranged carboxylic acids in excellent yield, without sacrificing the electrocatalyst.
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