Regioselective protection at N-2 and derivatization at C-3 of indazoles

被引:59
作者
Luo, Guanglin [1 ]
Chen, Ling [1 ]
Dubowchik, Gene [1 ]
机构
[1] Bristol Myers Squibb Pharmaceut Res Inst, Dept Neurosci Chem, Wallingford, CT 06443 USA
关键词
D O I
10.1021/jo060607j
中图分类号
O62 [有机化学];
学科分类号
070303 ; 081704 ;
摘要
Indazoles are regioselectively protected at N-2 by a 2-(tri-methylsilyl) ethoxymethyl (SEM) group using novel conditions. The SEM group can efficiently direct regioselective C-3 lithiation, and the resulting nucleophile can react with a wide range of electrophiles to generate novel indazole derivatives. The SEM group can be removed by treatment with TBAF in THF or aqueous HCl in EtOH.
引用
收藏
页码:5392 / 5395
页数:4
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