CN105085215A - Method for preparing 2-bromo-5-methoxybenzaldehyde - Google Patents

Abstract

The invention discloses a method for preparing 2-bromo-5-methoxybenzaldehyde. The method is characterized by comprising the following steps: (1) putting a compound 1 into a 2,000mL three-mouthed flask, then, adding 380mL of anhydrous dichloromethane into the three-mouthed flask, cooling the three-mouthed flask to the temperature of 0 DEG C, dropwise adding Br2 to the three-mouthed flask at the temperature of 0 DEG C, and after completing dropwise adding, restoring the temperature of the three-mouthed flask to room temperature and maintaining the conditions overnight; at the next day, heating the three-mouthed flask to the temperature of 30 DEG C, carrying out a reaction for 1 hour, and carrying out TLC (PE:EA=3:1) to indicate the finish of the reaction; and (2) after completing the reaction, washing the reaction solution with 5% Na2S2O3 until the reaction solution is free of bromine, then, washing a DCM phase twice with saturated NaHCO3, separating liquid, drying an organic phase with anhydrous Na2SO4, and carrying out spin-drying, so as to obtain 116g of crude product; and carrying out recrystallization with 200mL of PE, thereby obtaining a pure product which is white solid. According to the method, synthesis conditions and raw materials for a 2-bromo-5-methoxybenzaldehyde synthesis process and nuclear magnetic resonance spectra of synthesized products are provided, so that a detailed support is provided for analyzing and identifying all products in the synthesis process.

Description

The preparation method of the bromo-5-methoxybenzaldehyde of 2-

Technical field

The invention belongs to field of compound preparation, the preparation method of the bromo-5-methoxybenzaldehyde of especially a kind of 2-.

Background technology

At present, because Bioexperiment makes new breakthroughs, make us in treatment and find in the process of the cause of disease, means are more, result is more accurate, property pharmaceutical requirements is also increased gradually so for the various disease for the treatment of, therefore, the various compound with New function is developed a large amount of, the whole world all has in searching the new compound resisting various difficult and complicated cases, in the process so developed at these new compounds, the compound of numerous new textures and new configuration can be produced, and then find useful in the new compound that these are numerous, there is the molecule for the treatment of use, therefore developing new compound is one and important process.

2-bromo-5-methoxybenzaldehyde is a kind of important synthetic intermediate.

Summary of the invention

The object of the present invention is to provide the preparation method of the bromo-5-methoxybenzaldehyde of a kind of 2-, synthesis step of the present invention is simple, finished product yield is high, foreign matter content is low.

The object of the invention is to be achieved through the following technical solutions:

A preparation method for the bromo-5-methoxybenzaldehyde of 2-, is characterized in that: step is as follows:

(1) load 1 in 2000mL there-necked flask, then, add 380mL anhydrous methylene chloride, be cooled to 0 DEG C, drip Br in 0 DEG C ₂, after dropwising, return to ambient temperature overnight; Second day, be warming up to 30 DEG C, react 1 hour, TLC, PE:EA=3:1, display reaction is complete;

(2) react complete, with 5%Na2S2O3 washing reaction liquid to without bromine, then, wash DCM phase 2 times with saturated NaHCO3, separatory, by the dry organic phase of anhydrous Na 2SO4, be spin-dried for, obtain crude product 116g; Use 200mLPE recrystallization, obtaining sterling is white solid.

And the structure of described compound 1 is

Advantage of the present invention and positively effect are:

1, the productive rate of the 2-bromo-5-methoxybenzaldehyde of the present invention's synthesis is high, and crystallization effect is good, and purity is high, for follow-up chemistry and Bioexperiment provide highly purified standard specimen or sample.

2, the invention provides synthesis condition, the raw material in 2-bromo-5-methoxybenzaldehyde building-up process, and the nuclear-magnetism figure of synthesis after product, for the analysis and identification of product each in building-up process provides detailed support.

Accompanying drawing explanation

Fig. 1 is the nuclear-magnetism figure of the bromo-5-methoxybenzaldehyde of 2-of this preparation method synthesis.

Embodiment

Below in conjunction with embodiment, the present invention is further described, and following embodiment is illustrative, is not determinate, can not limit protection scope of the present invention with following embodiment.

Synthetic route of the present invention is as follows:

The preparation method of the bromo-5-methoxybenzaldehyde of 2-, step is as follows:

(1) load 1 (74.00g, 543.53mmol) in 2000mL there-necked flask, then, add 380mL anhydrous methylene chloride, be cooled to 0 DEG C, drip Br2 (86.86g, 543.53mmol) in 0 DEG C, after dropwising, return to ambient temperature overnight; Second day, be warming up to 30 DEG C, react 1 hour, TLC (PE:EA=3:1) display reaction is complete;

(2) react complete, with 5%Na2S2O3 washing reaction liquid to without bromine, then, wash DCM phase 2 times with saturated NaHCO3, separatory, by the dry organic phase of anhydrous Na 2SO4, be spin-dried for, obtain crude product 116g; Use 200mLPE recrystallization, obtaining sterling (1158060020A, 88g, 75.29%) is white solid.

NotebookPage:1158-0601HNMR:1158060020A(300MHz,CDCl3)。

Claims (2)

1. a preparation method for the bromo-5-methoxybenzaldehyde of 2-, is characterized in that: step is as follows:

(1) load 1 in 2000mL there-necked flask, then, add 380mL anhydrous methylene chloride, be cooled to 0 DEG C, drip Br in 0 DEG C ₂, after dropwising, return to ambient temperature overnight; Second day, be warming up to 30 DEG C, react 1 hour, TLC, PE:EA=3:1, display reaction is complete;

(2) react complete, with 5%Na2S2O3 washing reaction liquid to without bromine, then, wash DCM phase 2 times with saturated NaHCO3, separatory, by the dry organic phase of anhydrous Na 2SO4, be spin-dried for, obtain crude product 116g; Use 200mLPE recrystallization, obtaining sterling is white solid.

2. to go the preparation method of the bromo-5-methoxybenzaldehyde of the 2-described in 1 according to right, it is characterized in that: the structure of described compound 1 is