Reactions with Oxidising and Reducing Agents

Hydrodesulfurisation of benzothiophenes is conveniently achieved using Raney nickel, and before the advent of modern spectroscopic methods was utilised in the determination of structure of substituted benzothiophenes by conversion to a recognisable derivative. 

Reduction of the hetero-rings of both benzofuran and benzothiophene, notably with retention of the sulfur in the latter case, can be achieved using triethylsilane in acidic solution giving 2,3-dihydro-derivatives. 2,3-Dihydroxylation of benzofuran and benzothiophene can be achieved using Pseudomonas putida S-oxidation of the sulfur in the latter heterocycle using the same microbiological method has also been reported.  

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