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New Carbanionic Access to 3-vinylindoles and 3-vinylbenzofurans

Frédéric Le Strat, Jacques Maddaluno

Org Lett. 2002 Aug 8;4(16):2791-3.

PMID: 12153236

Abstract:

[reaction: see text] A simple route to 3-vinylbenzofurans, 3-vinylfuropyridines, and 3-vinylindoles from readily accessible acetylenic precursors is described. A standard halogen-lithium exchange triggers an irreversible addition on the triple bond, according to a 5-exo-dig heterocyclization process, followed by a lithium ethoxide elimination. A final isomerization of the exocyclic allene provides a 1,3-dienic system that can react with acrylates, in thermal or hyperbaric conditions, to provide the expected [4+2] cycloadducts.

Chemicals Related in the Paper:

Catalog Number Product Name Structure CAS Number Price
AP2388070-A Lithium ethoxide Lithium ethoxide 2388-07-0 Price
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