Synfacts 2010(12): 1346-1346  
DOI: 10.1055/s-0030-1258956
Synthesis of Heterocycles
© Georg Thieme Verlag Stuttgart ˙ New York

Synthesis of Indoles from 2-Azidoacrylate and ortho-Silyl Aryltriflates

Contributor(s): Victor Snieckus, Cédric Schneider
D. Hong, Z. Chen, X. Lin*, Y. Wang*
Zhejiang University, Hangzhou, P. R. of China
Further Information

Publication History

Publication Date:
22 November 2010 (online)

Significance

Reported is an efficient synthesis of substituted indoles 3 from the CsF- and Ph3P-mediated reaction of 2-azidoacrylates 1 with ortho-silyl aryltriflates 2. The reaction involves the formation of iminophosphorane (detected by HRMS and ³¹P NMR spectroscopy) and benzyne intermediates and subsequent annulation-hydrolysis-air oxidation. After screening of solvent and Ph3P loading, the scope of this reaction was demonstrated for various ethyl 2-azidoacrylates 1 and substituted ortho-silyl aryltriflate 2. 1,2-Naphthalyne and ortho-MeO benzyne precursors were shown to provide a single product, respectively, whose structures were confirmed by X-ray analysis.