Extrusion of dinitrogen from enol diazoacetates with a RhII catalyst generates metal enolcarbenes. Subsequent vinylogous addition of these to N‐acyliminopyridinium ylides results in an effective formal [3+3] cycloaddition to give highly substituted 1,2,3,6‐tetrahydropyridazines in up to 98 % ee and high yield.
Pericyclic Reaction of a Zwitterionic Salt of an Enedione-diazoester. A Novel Strategy for the Synthesis of Highly Functionalized Resorcinols
作者:Yu Liu、Kanwarpal Bakshi、Peter Zavalij、Michael P. Doyle
DOI:10.1021/ol101744h
日期:2010.10.1
Enedione-diazoesters formed from 3-TBSO-2-diazo-3-butenoates undergo base-catalyzed pericyclization that with dinitrogen extrusion and methyl migration provide a novel and efficient route to 2-carboalkoxyresorcinols. Intercepting the intermediate enolate anion with methyl vinyl ketone leads to the corresponding 4-substituted 2-carboalkoxyresorcinol and suggests generalization of this methodology.