A ring closing metathesis-manganese dioxide oxidation sequence for the synthesis of substituted pyrroles

The combination of ring closing, or enyne metathesis with oxidation in order to prepare N-sulfonyl pyrroles is described. Reasonable to good yields were obtained for a variety of substituents and the procedure may also be conducted in one-pot. 2-Bromo N-sulfonyl adducts prepared in this manner were subjected to an intramolecular Heck-type cyclisation, forming cyclic sulfonamides.

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