Regioselective intramolecular dipolar cycloaddition of azides and unsymmetrical alkynes.

Org Lett

Department of Chemistry and Center for Chemical Methodology and Library Development, Metcalf Center for Science and Engineering, 590 Commonwealth Avenue, Boston University, Boston, Massachusetts 02215, USA.

Published: January 2010

Enantioenriched allenylsilanes are used in three-component propargylation reactions with aldehydes and silyl ethers to form syn-homopropargylic ethers that contain an imbedded azide. These materials then undergo thermally induced intramolecular 1,3-dipolar cycloaddition reactions, resulting in unique fused ring systems containing 1,2,3-triazoles. The ability to modify all three components of the reaction allows for expedient access to compounds containing significant structural and stereochemical variation.

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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3164318PMC
http://dx.doi.org/10.1021/ol902681tDOI Listing

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