Synthesis of 2‐Aryl‐2,3‐dihydro‐1,8‐naphthyridin‐4(1H)‐ones by Deprotective Cyclization of N‐{3‐[(2E)‐3‐Arylprop‐2‐enoyl]pyridin‐2‐yl}‐2,2‐dimethylpropanamides in Water |
| |
| Authors: | Kazuhiro Kobayashi Risa Kosuna Ayumi Imaoka |
| |
| Affiliation: | 1. +81‐857‐315263;2. Division of Applied Chemistry, Department of Chemistry and Biotechnology, Graduate School of Engineering, Tottori University, Tottori, Japan |
| |
| Abstract: | A new and convenient method for the preparation of 2‐aryl‐2,3‐dihydro‐1,8‐naphthyridin‐4(1H)‐ones 4 has been developed. Thus, N‐{3‐(2E)‐3‐arylprop‐2‐enoyl]pyridin‐2‐yl}‐2,2‐dimethylpropanamides 3 are synthesized from commercially available pyridin‐2‐amine using an easily performed three‐step sequence and are subjected to cyclization with deprotection under acidic conditions in H2O to give the desired products. Similarly, 2‐aryl‐2,3‐dihydro‐1,7‐naphthyridin‐4(1H)‐ones 8 and 2‐aryl‐2,3‐dihydro‐1,6‐naphthyridin‐4(1H)‐ones 12 can be prepared from pyridin‐3‐amine and pyridin‐4‐amine, respectively. |
| |
| Keywords: | 2 3‐Dihydro‐1 6‐naphthyridin‐4(1H)‐ones 2 3‐Dihydro‐1 7‐naphthyridin‐4(1H)‐ones 2 3‐Dihydro‐1 8‐naphthyridin‐4(1H)‐ones Pyridinamines Lithiated pyridines |
|
|
