Synthesis of 2-Substituted Pyridines via a Regiospecific Alkylation, Alkynylation, and Arylation of Pyridine N-Oxides
Hans Andersson, Fredrik Almqvist* and Roger Olsson
*Department of Chemistry, Umeň University, SE-901 87 Umeň, Sweden, Email: fredrik.almqvistchem.umu.se
H. Andersson, F. Almqvist, R. Olsson, Org. Lett., 2007, 9, 1335-1337.
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Addition of Grignard reagents to pyridine N-oxides in THF at room temperature and subsequent treatment with acetic anhydride at 120░C afforded 2-substituted pyridines in good yields. By exchanging acetic anhydride for DMF in the second step, 2-substituted pyridine N-oxides were obtained, enabling the synthesis of 2,6-disubstituted pyridines.
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Pyridines, N-Oxides, Microwave Synthesis, Grignard Reagents