Background and overview[1]
Phenol-4-sulfonic acid can be used as a pharmaceutical synthesis intermediate. If phenol-4-sulfonic acid is inhaled, move the patient to fresh air; if skin contact occurs, remove contaminated clothing, rinse skin thoroughly with soap and water, and seek medical attention if you feel unwell.
Preparation[1]
Method 1: Synthesis of phenol-4-sulfonic acid: Take 100g mesitylene, add 78g phenol into it, heat the water bath to 65°C, add 4g phosphorous acid as a catalyst, and add the raw materials into the feed tank at one time. Add 82g of concentrated sulfuric acid to the concentrated sulfuric acid feed tank so that n(H2SO4):n(C6H6O)=1:1, n(C9H12):n(C6H6O)=1:1. Raise temperature to 100°C. Turn on the stirring paddle and the hypergravity reactor, adjust the rotor speed of the hypergravity reactor, and maintain the rotation speed of the hypergravity reactor 10 at 2000 rpm. After the temperature and equipment are stable, start feeding at a feeding speed of 250 mL/min. After the feeding is completed, cycle for 3 minutes to prepare phenol-4-sulfonic acid.
Method 2: Weigh 1325kg of liquefied phenol and 1550kg of 98% concentrated sulfuric acid respectively. Put the liquefied phenol into the sulfonation kettle, raise the temperature to 60°C, slowly add concentrated sulfuric acid dropwise and control it to finish within 30 minutes, keeping the temperature not exceeding 80°C. After finishing dropping the concentrated sulfuric acid, increase the temperature to 90°C, and carry out the sulfonation reaction for 2 hours. , to obtain phenol-4-sulfonic acid.
Method 3: Add phenol to a four-necked flask and heat it to melt it. After the phenol melts, add 8.5 to 10.5% of the mass of phenol concentrated sulfuric acid (mass percentage concentration is 98%) while stirring, and raise the temperature to 100 to 110 The sulfonation reaction takes place for 1.0 to 1.5 hours at ℃ to generate phenol-4-sulfonic acid from part of the phenol. Note that the sulfonation reaction temperature is controlled above 100°C. Below this temperature, ortho-position sulfonation products will be generated because para-position sulfonation products are mainly needed.
Main reference materials
[1]CN201710271862.1 A method for synthesizing bisphenol S in a hypergravity reactor
[2]CN201410831025.6 Preparation method of naphthalene-based water reducing agent
[3]CN201310533430.5 Preparation method of high-performance resin adhesive for rock wool sizing