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
1-(1-Alkoxyalkyl)-1H-1,2,4-triazoles (4) were prepared by treating acetals (1) with 1H-1,2,4-triazole (2) in the presence of pyridinium p-toluenesulfonate (3). The alkoxy group of 4 was substituted with -NR4 COR3 group by treating with carboxamides to give various 1-(1-acylaminoalkyl)-1H-1,2,4-triazole (6) in variable yields.
OHTA, SHUNSAKU;MARUYAMA, AKIHIKO;KAWASAKI, IKUO;HATAKEYAMA, SHOKO;ICHIKAW+, HETEROCYCLES, 31,(1990) N1, C. 2029-2036