One-pot synthesis of pyrrole-2-carboxylates and -carboxamides via an electrocyclization/oxidation sequence
Dennis Imbri1, Natalie Netz, Murat Kucukdisli
1Institute of Organic Chemistry, University of Mainz , Duesbergweg 10-14, D-55128 Mainz, Germany.
Abstract:
An electrocyclic ring closure is the key step of an efficient one-pot method for the synthesis of pyrrole-2-carboxylates and -carboxamides from chalcones and glycine esters or amides. The 3,4-dihydro-2H-pyrrole intermediates generated in situ are oxidized to the corresponding pyrroles by stoichiometric oxidants or by catalytic copper(II) and air in moderate to high yields. A wide range of functional groups are tolerated, and further combination with an in situ bromination gives access to polyfunctional pyrrole scaffolds.
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