Phenol red is a triphenylmethane-type organic reagent with a molecular formula of C19H14O5S and a molecular weight of 354.38. It is a red to dark red crystalline powder. It is stable under average temperature and pressure, but it must be kept away from solid oxidants and sealed in a cool place. Soluble in ethanol, sodium hydroxide, and sodium carbonate solution, insoluble in chloroform
and ether. Slightly soluble in water, easily soluble in ethanol and alkali solution, 1g of this product is soluble in 1300ml of water, about 350ml of alcohol, 500ml of acetone, almost insoluble in ether and chloroform, soluble in alkali hydroxide or alkali carbonate solution, dark red, stable in air. It is used as raw material for producing phenolic resin, kapuron, and adipic acid, as well as in the plastic and pharmaceutical industries. Acid-base indicator; Determination of total blood carbon dioxide; Indicator for preparing disaccharide urea culture medium in bacterial serum test.
There are several synthetic routes for It. We will list two again for illustration.
1. Heat 50g of o-sulfonylbenzoic anhydride and 70g of phenol to dissolve them. Add 50g of anhydrous zinc chloride and react at 135 ~ 140 ℃ for 7 hours. After the reaction, pour the reactant into hot water and stir quickly to disperse the crystalline product until there is no phenol smell. Or steam distillation to remove residual phenol. The crystalline solid is separated by filtration, and the crude product is obtained by thoroughly washing with water. The natural product can be dissolved with 10% dilute alkali, filtered, and then acid analyzed to obtain acceptable It.
2. (1) add 500g of crude phthaloylsulfonyl anhydride, 700g of phenol, and 500g of anhydrous zinc chloride into a 5000ML three-port flask, heat slightly to melt the phenol, and heat and stir at 130135 ℃ for 34 hours. If there is foam, add a few drops of ethanol. Cool it first, then heat it if the foam doesn't disappear. After the reaction, stir it from time to time to disperse the product;
(2) pour the product into a 5000ML beaker while it is hot, wash the flask with warm water (3040 ℃), filter and crystallize, and wash twice with water;
(3) transfer the sediment to a beaker, add 2000ml of 10% sodium carbonate solution, heat for 2 minutes, a place for 5 minutes, filter, and then wash with water twice;
(4) slowly stir the filtrate and add it to dilute hydrochloric acid (200ml concentrated hydrochloric acid and 300ml water). In the case of foam, heat it for starting, heat it for 6080 ℃, cool it, filter and collect the sediment, wash it with water twice, and dry it. The obtained. It is a red powder with a yield of 450550g.
It is mainly used as an acid-base indicator and a reagent for liver function tests and chromatographic analysis. It is a kind of acid-base indicator. The acid-base hand usually refers to a type of substance that changes color with the change of pH value of the solution. It is an indispensable chemical in the field of chemical analysis. This indicative color change results from the structural transformation of the "tautomer." It is widely used as an acid-base indicator. It is commonly used in the auxiliary diagnosis of renal function. Its monosodium salt is used by veterinarians for renal function tests, chromatography reagents, etc., and can also be used to determine total carbon dioxide in the blood, an indicator of disaccharide iron urea culture medium, etc.
Phenol red has a strong corrosive effect on skin and mucous membrane, inhibiting the central nervous system or damaging liver and kidney functions. Acute poisoning: inhalation of high concentration steam may cause headache, dizziness, fatigue, blurred vision, pulmonary edema, etc. Ingestion by mistake may cause digestive tract burns, burning pain, phenol smell in exhalation, blood in vomitus or stool, possible gastrointestinal perforation, shock, pulmonary edema, liver or kidney damage, acute renal failure, and death from respiratory failure. Eye contact may cause burns. Burned skin can absorb it and cause acute renal failure after a certain incubation period. Chronic poisoning: can cause headache, dizziness, cough, anorexia, nausea, vomiting, and proteinuria in severe cases. It May cause dermatitis. In case of any of the above conditions, treatment measures shall be taken immediately. Skin contact: immediately remove the contaminated clothes, wipe them with glycerin, polyethylene glycol, or polyethylene glycol and alcohol mixture (7:3), and wash them thoroughly. Or flush with a large amount of flowing water for at least 15 minutes. Seek medical attention. Eye contact: immediately lift the eyelids and thoroughly wash them with a large amount of flowing water, chemicalbook, or normal saline for at least 15 minutes. Seek medical attention. Inhalation: quickly leave the site to a place with fresh air. Keep respiratory tract unobstructed. If breathing is difficult, give oxygen. If breathing stops, give artificial respiration immediately. Seek medical attention. Ingestion: immediately drink 15 ~ 30ml of vegetable oil. Induce vomiting. Seek medical attention.