Stereocontrolled synthesis of linear 22R-homoallylic sterols via a triflic acid-catalyzed 2-oxonia cope rearrangement

被引:29
作者
Loh, TP [1 ]
Hu, QY [1 ]
Ma, LT [1 ]
机构
[1] Natl Univ Singapore, Dept Chem, Singapore 117543, Singapore
关键词
D O I
10.1021/ol026136e
中图分类号
O62 [有机化学];
学科分类号
070303 ; 081704 ;
摘要
[GRAPHICS] Poor stereoselectivity caused by the involvement of side reaction pathways was observed in the ln(OTf)(3)-catalyzed allyl-transfer reaction (R = electron-withdrawing group). Subsequently, it was found that the employment of triflic acid (TFA) as catalyst could successfully suppress the side reaction pathways and, hence, achieve high stereoselectivity.
引用
收藏
页码:2389 / 2391
页数:3
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