2,3-二甲基-4-氯吡啶-N-氧化物的合成工艺改进

Process Improvement on the Synthesis of 4-Chloro-2,3-dimethylpyridine-N-oxide

对2,3-二甲基-4-氯吡啶-N-氧化物(4)的合成工艺进行了改进。以2,3-二甲基吡啶为原料,经氧化(钨酸钠为催化剂,双氧水为氧化剂,收率96.5%),硝化(65%的浓硝酸为硝化剂,收率86.3%,纯度99.0%)及氯化(乙酰氯为氯化剂,收率86.8%,纯度98.6%)合成了4,总收率72.2%,4的结构经1H NMR表征。

4-Chloro-2,3-dimethylpyridine-N-oxide（ 4 ） were synthesized from 2,3 -dimethylpyridine by the reaction of oxidation （sodium tungstate as a catalyst, hydrogen peroxide as a oxidant, yield of 96.5% ）, nitration（65% nitric acid as a nitrating agent, yield of 86.3%, purity of 99.0% ） and chlorination（ acetyl chloride as a chloridizing agent, yield of 86.8%, purity of 98.6% ）. The overall yield reached 72.2%. The structure of 4 was identified by ^1H NMR.