77 results about "Tetralones" patented technology

The invention discloses a preparation method of 3-bromo-1,3,4,5-tetrahydro-2H-benzazepine-2-keto. The preparation method comprises the following stages: alpha-tetralone preparation stage, 2-bromo-3,4-dihydro-N-hydroxy-(2H)-naphthalimide preparation stage and 3-bromo-1,3,4,5-tetrahydro-2H-1-benzazepine-2-keto, wherein the alpha-tetralone preparation stage comprises the following steps: after mixing gamma-butyrolactone, benzene and aluminum chloride anhydrous, raising the temperature to be 60-90 DEG C, and preserving the temperature for reaction for 5-30 hours; after the reaction is finished, performing hydrolysis, layering and washing on 25 parts of 6% hydrochloric acid solution until neutral; and then distilling to remove excessive benzene, and performing high vacuum rectification to obtain alpha-tetralone. Then, the finished product is finally prepared through a bromination reaction, an oximation reaction and a beckmann rearrangement reaction, the purity of the finished product is high, and the yield is as high as more than 90%. Moreover, the production technology is simple, the production cost is low, and the pollution is little.