| 摘要 |
<p>An improved process for the preparation of 2-chloro-3-amino-4-methylpyridine (CAPIC) which comprises the following steps: (a) reacting acetylacetaldehyde dimethyl acetal with malononitrile to yield a mixture of 4,4-dicyano-3-methyl-3-butenal dimethyl acetal and 1,1-dicyano-4-methoxy-2-methyl-1, 3-butadiene, (b) treating the mixture of 4,4-dicyano-3-methyl-3-butenal dimethyl acetal and 1, 1-dicyano-4-methoxy-2-methyl-1,3-butadiene so produced with a strong acid and water, to yield 3-cyano-4-methyl-2-pyridone, (c) treating the 3-cyano-4-methyl-2-pyridone with a strong chlorinating agent, to yield 3-cyano-2-chloro-4-methylpyridine, (d) treating the 3-cyano-2-chloro-4-methylpyridine with a strong acid and water, to yield 2-chloro-3-amido-4-methylpyridine, and (e) treating the 2-chloro-3-amido-4-methylpyridine with a strong base and a halide, to yield 2-chloro-3-amino-4-methylpyridine.</p> |
