A simple one-pot synthesis of benzoxazine- 2,4-diones and benzothiazine-2,4-diones was written by Zhu, Xiaoxiang;Yu, Qian-Sheng;Greig, Nigel H.;Flippen-Anderson, Judith L.;Brossi, Arnold. And the article was included in Heterocycles in 2003.Application of 28020-37-3 This article mentions the following:
A simple and efficient procedure has been developed for a one-pot synthesis of substituted benzoxazine-2,4-diones and benzothiazine-2,4-diones directly from salicylic acid (or thiosalicylic acid) and amines. The reaction of [2-(chlorocarbonyl)phenyl]carbonic acid Me ester with 3,4-dimethoxybenzeneethanamine gave 2-(acetyloxy)-N-[2-(3,4-dimethoxyphenyl)ethyl]benzamide. Deprotection of this gave 2-hydroxy-N-[2-(3,4-dimethoxyphenyl)ethyl]benzamide and sequential cyclocondensation with carbonochloridic acid Et ester gave 3-[2-(3,4-dimethoxyphenyl)ethyl]-2H-1,3-benzoxazine-2,4(3H)-dione (I). A similar reaction sequence starting from 2-mercaptobenzoic acid gave 3-(phenylmethyl)-2H-1,3-benzothiazine-2,4(3H)-dione (II). In the experiment, the researchers used many compounds, for example, 3-Amino-2,6-dimethoxypyridine (cas: 28020-37-3Application of 28020-37-3).
3-Amino-2,6-dimethoxypyridine (cas: 28020-37-3) belongs to pyridine derivatives. Pyridine has a dipole moment and a weaker resonant stabilization than benzene (resonance energy 117 kJ璺痬ol閳? in pyridine vs. 150 kJ璺痬ol閳? in benzene). Halopyridines are particularly attractive synthetic building blocks in a variety of cross-coupling methods, including the Suzuki-Miyaura cross-coupling reaction.Application of 28020-37-3