manufacture of pharmaceuticals, thioindigo.
1-Benzothiophene has the odour of naphthalene. If the IR spectrum is not very good, then suspend it in a faintly alkaline aqueous solution and steam distil it. Extract the distillate with Et2O, dry the extract (CaCl2), filter, evaporate the solvent and fractionate the residue. The distillate sets solid. The sulfoxide has m 142o, the picrate has m 148-149o (yellow crystals from EtOH) and the styphnate has m 136-137o. [Hansch & Lindwall J Org Chem 10, 381 1945, Meyer & Meyer Chem Ber 52B 1249 1919, Weisgerber & Kruber 53 1551 1920, Iddon & Scrowston Adv Heterocycl Chem 11 177 1970, Beilstein 17/2 V 6.]
WHITE TO RED CRYSTALLINE LOW MELTING SOLID
Benzo[b]thiophene has application in organic as well as pharmaceutical industry as a component in the synthesis of Raloxifene, a breast cancer therapeutic, or hydrodesulfurization reactions.