Cycloisomerization of aromatic homo-and bis-homopropargylic alcohols via catalytic Ru vinylidenes: formation of benzofurans and isochromenes

A Varela-Fernández, C González-Rodríguez…

Index: Varela-Fernandez, Alejandro; Gonzalez-Rodriguez, Carlos; Varela, Jesus A.; Castedo, Luis; Saa, Carlos Organic Letters, 2009 , vol. 11, # 22 p. 5350 - 5353

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Citation Number: 65

Abstract

Ru-catalyzed cycloisomerizations of aromatic homo-and bis-homopropargylic alcohols effectively afford benzofurans and isochromenes. These processes proved to be chemo-and regioselective (5-, and 6-endo cyclizations) derived from key Ru vinylidene intermediates. The presence of an amine/ammonium base− acid pair is crucial for the catalytic cycle.

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Torquoselectivity in the electrocyclic conversion of benzocy...

[Jefford, Charles W.; Bernardinelli, Gerald; Wang, Ying; Spellmeyer, David C.; Buda, Andrzej; Houk Journal of the American Chemical Society, 1992 , vol. 114, # 4 p. 1157 - 1165]

New syntheses of isochromene

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Synthesis and structure–activity relationships of selective ...

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