Preparation method of anhydrous system o-nitroanisole

Abstract

The invention discloses a preparation method of anhydrous system o-nitroanisole, which comprises the following steps: mixing and stirring o-nitro benzene chloride, methanol, and an alkalization deacidification agent, heating the mixture with a heating speed of 30 DEG C / h for reflux reaction, controlling the temperature at 40-80 DEG C, performing the reflux reaction for 2-10 h, filtering, recovering methanol, performing reduced-pressure distillation to obtain the product of o-nitroanisole. The invention obtains the product by directly heating o-nitro benzene chloride, methanol, and an alkali; after the reaction, the reaction solution is directly pressed into a storage groove for precipitation; methanol is recovered (by direct recycle); the obtained product and unreacted o-nitro benzene chloride (for recycle) are treated by rectification; the utilization rate of o-nitro benzene chloride reaches above 98%, and the yield of o-nitroanisole reaches 93%-95%; the utilization rate of methanol is greatly increased; the process steps are reduced; the distillation is reduced; the energy consumption is saved; and waste water generated during a traditional process is converted into solid wastes. Compared with the traditional processes, the invention has the advantages of short process, low energy consumption, high utilization rate of o-nitro benzene chloride, and less pollution.

Description

technical field [0001] The invention relates to a preparation method of anhydrous o-nitroanisole. Background technique [0002] O-nitroanisole, as an important dyestuff, medicine, and organic intermediate, can be used to synthesize anthranil, guaiacol, etc. At present, there are two main routes for the existing production process: [0003] 1. [0004] Using phenol as raw material, after methylation, it is directly nitrated to obtain the ortho-para nitrated compound, and then separated to obtain the product. [0005] 2. [0006] Using chlorobenzene as raw material, it is first nitrated and then etherified to obtain o-nitroanisole. [0007] In the second process, the traditional process is obtained by heating o-nitrochlorobenzene with water, sodium hydroxide and methanol. The resulting reaction solution needs to recover the mixed solution of methanol and water, then separate the liquids, and rectify to obtain o-nitroanisole, and the mixing ratio of methanol and water ...

AI Technical Summary

Problems solved by technology

The resulting reaction solution needs to recover the mixed solution of methanol and water, then separate the liquids, and rectify to obtain o-nitroanisole, and the mixing ratio of methanol and water obtained in the process is different, so it needs to be rectified to reclaim methanol (retaining applied), or applied directly, but the material ratio of the reaction system will change, which will lead to poor process stability