陳焜銘Kwun-min Chen杜懿珊Duh, Yih-Shan2020-12-142020-08-252020-12-142020http://etds.lib.ntnu.edu.tw/cgi-bin/gs32/gsweb.cgi?o=dstdcdr&s=id=%22G060742031S%22.&http://rportal.lib.ntnu.edu.tw:80/handle/20.500.12235/111140本題目為利用有機催化反應,合成四取代1,3,4,5-吡唑化合物。在此反應中,以20 mol% DL-脯胺酸為催化劑,進行巴豆醛及苯腙之 [3+2]-環加成反應,芳香化後得到產物吡唑,產率30-51%。DL-脯胺酸首先活化巴豆醛,生成亞胺離子中間體,與苯腙進行 [3+2]-環化反應,芳香化後,便得到四取代吡唑化合物。An organocatalytic synthesis of 1,3,4,5-tetrasubstituted pyrazole was described. In this study, 20 mol% DL-proline catalyzed the [3+2] cycloaddition of crotonaldehyde with phenylhydrazone followed by aromatization, leading to the pyrazole formation in moderate yield (30-51%). DL-proline activated crotonaldehyde by in situ generation of imium ion intermediate, so that the [3+2] cyclization with phenylhydrazone and aromatization could proceed.nonenone有機催化α,β-不飽和醛及2-羥基苯甲醛苯腙製備四取代1,3,4,5-吡唑化合物Organocatalytic Synthesis of 1,3,4,5-Tetrasubstituted Pyrazole from α,β-Unsaturated Aldehyde and 2-Hydroxybenzaldehyde Phenylhydrazone