Study On New Methods Of Synthesis Methyl Benzoquate

The quinoline's derivatives which are one family of anticoccidal drugs were researched early and their effects are excellent. Up to the present, several drugs of them are still added to food to prevent or cure coccidiosis. Methylbenzoquate that is one of the quinoline's derivatives has been used as an anticoccidal drug because of its strong effect.The key step for preparation of methylbenzoquate is synthesis of 3-benzyloxy-4-butylbenzenamine.In literature, the intermediate is prepared with 3-aminophenol as the raw material by a series of reaction, such as acylation, Fries arrangement, catalytic hydrogenation, benzylation and hydrolyzation in a gross yield of 41.4%. However, this type of process are inefficient and expensive due to several, complicated operation steps, equipment wear, the high cost of Pd/C, and so on. In the new method, the process was optimized as follows: acylation, Fries arrangement, benzylation and reduction-hydrolyzation. In the acylation and Fried arrangement, the same solvent was used, which is more efficient for operation. In addition, the hydrazine hydrate which is cheaper substituted of Pd/C for reduction of carbonyl group. And the 3-benzyloxy-4-butylbenzenamine was obtained with gross yield of 47.3% .The methylbenzoquate is prepared with 3-benzyloxy-4-butylbenzenamine and dimethyl 2-(methoxymethylene)malonate as reactants by condensation and cyclization and the yield is 61% in literature. Compared to the literature, we obtained the methylbenzoquate with a higher yield of 67.7% in the optimized process.