Yb(OTf)3 catalyzed [1,3]-rearrangement of 3-alkenyl oxindoles
Chaofei Wu1, Junlin Wan1, Chao Song1
1College of Chemistry and Materials Science, Wenzhou University, Wenzhou 325035, PR China. junjiang@wzu.edu.cn.
Abstract:
A Yb(OTf)3 catalyzed [1,3]-rearrangement of 3-alkenyl oxindoles was achieved, affording a variety of multifunctional 3-ylideneoxindoles with good yields and Z/E selectivities (64%-89% yield, 78 : 22->99 : 1 Z/E). Importantly, an operationally simple, one-pot sequential catalytic synthesis of 3-ylideneoxindoles was also developed. Additionally, a cross [1,3]-rearrangement experiment and nonracemic transformation were also carried out, which indicated a concerted rearrangement mechanism of this methodology.
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