Uses
1-benzothiophene-3 (2H) - one is an organic intermediate, which can be prepared from 2-carboxymethyl thiobenzoic acid as starting material. It can be used to prepare fluorescent red 5B. Fluorescent red 5b is an oil-soluble solvent pigment with blue light, which has good heat resistance, light resistance, high coloring power and bright color; It can be used for coloring a variety of resins.
Synthesis Reference(s)
The Journal of Organic Chemistry, 10, p. 381, 1945
DOI: 10.1021/jo01181a001
Synthesis
Synthesis of 1-benzothiophene-3(2H)-one: 38 kg of 2-carboxymethylthiobenzoic acid and 33 kg of sodium hydroxide were weighed according to the proportional amount, and the above raw materials were mixed uniformly in a closed-loop kettle, heated up to 180 , and then carried out a closed-loop reaction, and the reaction time of the said closed-loop reaction was 9 hours. At the end of the closed-loop reaction, 75 kg of water was added to dilute the diluted solution, and the diluted solution was subjected to solid-liquid separation, the insoluble material was removed and the filtrate was collected to produce an aqueous solution of 1-benzothiophene-3(2H)-one.
