A Facile Synthesis of 1‐Substituted 3‐Alkoxy‐1H‐isoindoles Based on the Reaction of 2‐(Dialkoxymethyl)phenyllithiums with Nitriles,Followed by Acid‐Catalyzed Cyclization |
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| Authors: | Minami Kuroda Kazuhiro Kobayashi |
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| Affiliation: | Division of Applied Chemistry, Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, 4‐101 Koyama‐minami, Tottori 680‐8552, Japan, (phone/fax: +81‐857‐315263) |
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| Abstract: | 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 CHCl3 to give the desired products in reasonable yields. Similarly, 3‐aryl‐1‐ethoxy‐1‐methyl‐1H‐isoindoles 7 have been prepared starting from 1‐bromo‐2‐(1,1‐diethoxyethyl)benzenes 5 . |
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| Keywords: | 1H‐Isoindoles, 3‐alkoxy‐ Phenyllithium, 2‐(dialkoxymethyl)‐ |
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