Syntheses of 3,4-Disubstituted Pyrroles and Furans via Lewis Acid-Promoted Semipinacol Rearrangement/Alkyne-Ketone Metathesis Reaction of (C)-2-<i>N</i>- or <i>O</i>-((3-Arylpropargyl)methyl)-Tethered 3,5,5-Trimethyl-2,3-epoxycyclohexan-1-ones
作者:Ming-Chang P. Yeh、Ming-Nan Lin、Ching-Hsien Hsu、Chia-Jung Liang
DOI:10.1021/jo402025z
日期:2013.12.20
The synthesis of 2,3-disubstituted pyrroles via TMSOTf-assisted cyclization reaction of 3,5,5-trimethyl-2,3-epoxycyclohexan-1-ones incorporating a (3-arylpropargyltosylamino)methyl tether at the C-2 position is described. The reaction starts with an acid-promoted semipinacol rearrangement to give a ring contraction cyclopentanone moiety bearing an arylpropargylaminoacetyl side chain. A subsequent alkyne-ketone
描述了通过TMSOTf辅助的3,5,5-三甲基-2,3-环氧环己-1-酮在C-2位置掺入(3-芳基炔丙基甲苯磺酰基氨基)甲基系链的3,5,5-三甲基-2,3-环氧环己-1-酮的环化反应合成2,3-二取代的吡咯。该反应以酸促进的半松果酚重排开始,以给出带有芳基炔丙基氨基乙酰基侧链的环收缩环戊酮部分。随后的炔烃-酮复分解以良好的产率提供了吡咯衍生物。所述3,4-二取代的呋喃类似物也可以是可从3,5,5-三甲基-2,3- epoxycyclohexan -1-酮与栓系arylpropargyl甲基醚在C-2位和BF 3 ·OET 2下的氧气气氛。