Synthesis 2011(10): 1575-1580  
DOI: 10.1055/s-0030-1259997
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

m-Terphenyl Ethers, a New Hydroxy Protecting Group Cleavable under Reductive Single Electron Transfer Reaction Conditions

Ugo Azzena*, Sarah Mocci, Luisa Pisano*
Department of Chemistry, University of Sassari, via Vienna 2, 07100 Sassari, Italy
Fax: +39(79)229559; e-Mail: ugo@uniss.it; luisa@uniss.it;
Further Information

Publication History

Received 26 January 2011
Publication Date:
08 April 2011 (online)

Abstract

m-Terphenyl ethers and, to a lesser extent, 2,6-dimeth­oxyphenyl ethers, were tested as protected hydroxy derivatives under a variety of reaction conditions. These ethers underwent regioselective cleavage of the aromatic C(1)-O bond under reductive SET reaction conditions using alkali metals in tetrahydrofuran at room temperature. This deprotective procedure was efficiently realized in the presence of several other functional groups, including an acetal, a phenyl alkyl ether, an unprotected alcohol, and carbon-carbon double and triple bonds. Furthermore, m-terphenyl ethers proved stable under different reaction conditions, including acidic hydrolysis and formation and/or employment of different organometallic reagents.

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