Nitrogen's reactivity of various 3-alkoxypyrazoles

作者：Guillou Sandrine; Bonhomme Frederic J; Janin Yves L^*

来源：Tetrahedron, 2009, 65(13): 2660-2668.

DOI：10.1016/j.tet.2009.01.099

• 3-Alkoxypyrazole
• N-Arylation
• N-Alkylation

Our current interest in the design of original chemical libraries featuring a pyrazole nucleus led us to focus on the chemistry of the 3-alkoxy-5-methylpyrazoles we have recently made readily available. With in mind the preparation of an array of the less accessible 1-arylpyrazol-3-ones, the present report describes the respective nitrogen's reactivity of various 3-alkoxypyrazoles toward arylation reaction, using arylboronic acids, as well as alkylation reactions using methyl iodide or benzylbromide. The structure assignments of the isomers obtained were achieved using long distance (15)N-(1)H NMR correlation measurements or by the recourse to unambiguous synthetic pathways.

• 出版日期2009-3-28