How is 5-Fluoro-1-benzothiophene (CAS: 70060-12-7) typically synthesized?

5-Fluoro-1-benzothiophene can be synthesized via the halo substitution of 1-benzothiophene with hydrogen fluoride (HF) in the presence of a suitable catalyst such as iron trifluoromethanesulfonate. The reaction conditions typically involve heating the mixture to 100°C under an inert atmosphere. This method provides good yield and selectivity for the substitution product.