1,2-aryl and 1,2-hydride migration in transition metal complex catalyzed diazo decomposition: a novel approach to alpha-aryl-beta-enamino esters.
N-Tosyl diazoketamines were prepared by addition of the ethyl alpha-diazoacetate anion to N-sulfonylimines. The diazo decomposition of the diazoketamines with Rh(2)(OAc)(4) complex resulted in aryl migration to give alpha-aryl-beta-enamino esters in good yields and high stereoselectivity. The effect of the catalysts on the migratory aptitude of 1,2-aryl over 1,2-hydride migration was studied. A reaction mechanism involving a "bridged" phenonium ion is proposed. Reaction: see text.
Jiang
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Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of Education, Department of Chemistry, Peking University, Beijing 100871, China.
Qu
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Wang
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