A Facile Synthesis of 1-Substituted 3-Alkoxy-1<i>H</i>-isoindoles Based on the Reaction of 2-(Dialkoxymethyl)phenyllithiums with Nitriles, Followed by Acid-Catalyzed Cyclization
作者:Minami Kuroda、Kazuhiro Kobayashi
DOI:10.1002/hlca.201400333
日期:2015.3
A two‐step synthesis of 1‐substituted 3‐alkoxy‐1H‐isoindoles 4 has been developed. Thus, the reaction of 2‐(dialkoxymethyl)phenyllithium compounds, which are easily generated in situ by Br/Li exchange between 1‐bromo‐2‐(dialkoxymethyl)benzenes 1 and BuLi in THF at −78°, with nitriles afforded [2‐(dialkoxymethyl)phenyl]methanimines 2, which were treated with a catalytic amount of TsOH⋅H2O in refluxing
已开发出两步合成1-取代的3-烷氧基-1 H-异吲哚4的方法。因此,2-(二烷氧基)苯基的化合物,其是容易产生的反应在原位被Br /锂之间的交换的1-溴-2-(二烷氧基)苯1和BuLi的THF中,在-78℃,用得到腈[2 -(二烷氧基甲基)苯基]甲亚胺2,在回流的CHCl 3中用催化量的TsOH·H 2 O处理,以合理的收率得到所需的产物。同样,从1-溴-2-(1,1-二乙氧基乙基)苯5制备了3-芳基-1-乙氧基-1-甲基-1 H-异吲哚7。