The main properties of p-hydroxybenzaldehyde

P-hydroxybenzaldehyde, also known as p-formaldehyde phenol, 4-hydroxybenzaldehyde (PHBA for short), molecular formula CH6O is a white crystalline powder with aroma. Slightly soluble in cold water, soluble in hot water, alcohol and ether. The density of 116 ° C melting point sublimes under normal pressure without decomposition.

The median lethal dose (mouse, abdominal cavity) 500 mg/kg. It has a thorny number. Does not volatilize in water vapor. It reacts with ferric chloride to form lavender; it reacts with sodium amalgam to form 4,4 benzyl benzoin; and zinc and hydrochloric acid react to form p-cresol. It is present in the form of glycosides in a variety of plant hydrolysis, from needles in water; or from phenol and chloroform and pyridine. The synthesis method mainly comprises phenol, p-aminobenzaldehyde, p-nitrotoluene and p-cresol as raw materials to synthesize p-hydroxybenzaldehyde. It can be used as a raw material to synthesize perfumes such as vanillin, syringaldehyde, anisole, anisaldehyde and raspberry ketone.

In the pharmaceutical industry, it is used for the synthesis of amoxicillin, benzalkonium bromide, p-hydroxy-hydroxy acid, scorpion, rhododendron, artificial gastrodia, esmolol and the like. Also used in fungicides, photo emulsifiers, nickel plating brighteners, etc. P-hydroxybenzaldehyde is an important fine organic chemical product widely used in the fields of pharmaceutical pesticides, perfumes, petrochemicals, etc., and plays an increasingly important role in the fields of synthetic drugs and liquid crystals with the development of science and technology.

In recent years, with the rapid development of pharmaceutical, electronics, cosmetics and other industries, the domestic market demand for hydroxybenzaldehyde is increasing. The annual consumption is about 2,000 tons, of which more than 50% is used in the pharmaceutical industry, only for the production of sulfonamides. The annual demand for the synergist oxymethazine is more than 1,000 tons. Another major use of p-hydroxybenzaldehyde is the production of p-hydroxyphenylglycine, which is a key intermediate for the new semi-synthetic penicillin monohydroxyamethylene penicillin. Amoxicillin is an antibiotic that is currently used in large quantities and has good effects. However, the current domestic pharmaceutical grade p-hydroxybenzaldehyde products are still not relevant, mainly relying on imports.