Mechanism of 1,3-hydrogen migration in a gold bicyclo[3.2.0]heptene complex: The role of brønsted acid in the gold-catalyzed cycloisomerization of 7-aryl-1,6-enynes

Journal Article (Journal Article)

The gold 7-phenylbicyclo[3.2.0]hept-1(7)-ene complex 1 is generated as an intermediate in the gold-catalyzed cycloisomerization of 7-phenyl 1,6-enyne 2 to 7-phenylbicyclo[3.2.0]hept-1(7)-ene 3. We have investigated the kinetics of the isomerization of 1 via formal 1,3-hydrogen migration to form the corresponding gold 6-phenylbicyclo[3.2.0]hept-6-ene complex 4 to obtain direct experimental information regarding the mechanism by which 1 evolves into products. These experiments were in accord with conversion of 1 to 4 through a hidden Brønsted acid catalyzed pathway that occurred outside the coordination sphere of gold. Similarly, in situ spectroscopic analysis of the catalytic cycloisomerization of enyne 2 was consistent with a mechanism involving sequential gold-catalyzed cycloaddition followed by Brønsted acid catalyzed 1,3-hydrogen migration outside the coordination sphere of gold.

Full Text

Duke Authors

Cited Authors

  • Brooner, REM; Robertson, BD; Widenhoefer, RA

Published Date

  • November 24, 2014

Published In

Volume / Issue

  • 33 / 22

Start / End Page

  • 6466 - 6473

Electronic International Standard Serial Number (EISSN)

  • 1520-6041

International Standard Serial Number (ISSN)

  • 0276-7333

Digital Object Identifier (DOI)

  • 10.1021/om500815k

Citation Source

  • Scopus