Preparation and application of 5-chlorosalicylaldehyde

5-Chlorosalicylaldehyde is an organic intermediate that can be prepared from salicylaldehyde by chlorine chlorination. This product forms stable yellow Schiff bases with amines, which are used as protective groups in peptide synthesis. 5-Chlorosalicylaldehyde is mainly used as an intermediate in organic syntheses such as medicine, fragrance, and dye. The following will introduce the preparation method and application of 5-Chlorosalicylaldehyde.

Preparation of 5-Chlorosalicylaldehyde
Method one:
5-Chlorosalicylaldehyde

Pour the purified chlorine gas into salicylaldehyde, when the reaction solution turns bright yellow, finish the reaction, add 1 volume ratio of ethanol, heat up to 60°C, cool, slowly precipitate white crystals, suction filtration, and recrystallized from ethanol to obtain 5- Chlorsalicylaldehyde.

Method two:
5-Chlorosalicylaldehyde

Hexamethylenetetramine (2.86 g, 20 mmol) was added to a mixture of 4 Chlorophenol (2.2 g, 17 mmol) in TFA (10 mL) at 0 °C. The suspension was then heated keeping the temperature at 50-60°C and monitored by HPLC. No more starting material was present after 20 h. The solution was cooled and water (40 mL) was added followed by concentrated H2SO4 (1 mL). The mixture was stirred for another 1 h at RT, then more water (50 mL) was added and the aqueous solution was extracted with CH2Cl2 (3*40 mL). The combined organic phases were washed with brine, dried over Na2SO4, and concentrated to give 2.0 g of 5-Chlorosalicylaldehyde (75% yield, 95% purity).

5-Chlorosalicylaldehyde Application
5-Chlorosalicylaldehyde can be used to prepare 5-Chloro-2-benzofuranyl-p-chlorophenyl ketone. Benzofurans are compounds that exist widely in nature, including agonist estrogen receptor β subtype (estrogen receptor-torβ, ER13), antagonize thyroid hormone receptor (THR) and H3 receptor, inhibit histone Deacetylase (histone deacetylase, HDAC), anti-oxidative damage and anti-tumor and other physiological activities.

Suspend 1 mol of potassium hydroxide in ethanol, stir and heat to 50 ° C, take 0.8 mol of 5-Chlorosalicylaldehyde and slowly add it to the ethanol solution of potassium hydroxide, stir for 10 min, and add α-Bromoparaffin in batches at this temperature. Chloroacetophenone 0.9mol, added, heated to reflux for 3h, cooled, suction filtered, washed with dilute ethanol to obtain a white solid, recrystallized from ethyl acetate to obtain 5-Chloro-2-benzofuranyl-p-chlorophenyl ketone, Yield 90.3%.

The above is the preparation method and application of Guan 5-Chlorosalicylaldehyde, and I hope it will be helpful to everyone. Clent Chemical is a 5-Chlorosalicylaldehyde supplier, if you want to know more about 5-Chlorosalicylaldehyde, please continue to pay attention to our website. We will regularly update relevant articles and products, provide relevant product information and materials, and look forward to your visit and consultation.