有機催化合成1,3,4,5-四取代吡唑

多取代吡唑及其衍生物的製備對於合成天然物及製藥業來說是相當重要的一部分，早期合成吡唑時，對反應的條件相當嚴苛。本文以較溫和的方法，利用具有布朗斯特酸特性及氫鍵效應的有機催化劑聯萘酚磷酸酯催化由實驗室容易取得的2-羥基苯腙為起始物與具有拉電子基及各種官能基化的丙烯基醋酸酯，進行aza-麥可加成反應及環化加成反應，成功合成多取代的吡唑化合物。其反應受到官能基的立體效應影響較大，產率皆有不錯的表現(46-85%)。在聯萘酚磷酸酯 ( 5 mol% ) 的催化反應下，以甲醇作為反應溶劑，反應溫度為常溫，進行雜環化反應。

關鍵字

有機催化；磷酸；吡唑

並列摘要

The preparation of polysubstituted pyrazoles and their derivatives is a very important part of the synthesis of natural materials and the pharmaceutical industry. Compared with previous studies, we synthesized pyrazole in mild condition rather than harsh conditions. binaphthol phosphate, an organic catalyst with Bronsted acid properties and hydrogen bonding effect, is utilized. 2-hydroxyphenyl hydrazine which is easily obtained from the laboratory reaction with various functionalized propylene acetates featuring the electron-withdrawing group. Performing aza-Michael reaction and cycloaddition reaction yielded a polysubstituted pyrazole compound. The reaction is greatly affected by the stereo effect of the functional group, and the yield has a good performance (46-85%). Catalytic reaction was carried out in 5 mol% of binaphthol phosphate in methanol at a normal temperature.