The Triphenyl Phosphite-Chlorine Reagent in the Synthesis of Pyrroles from N-Allylamides

Abstract

A novel application of (PhO)₃P-Cl₂ chemistry to the synthesis of 2-substituted and 2,3-disubstituted pyrroles from N-allyl­amides is illustrated. A mild procedure is used to generate the imino chloride intermediates, which are subsequently cyclized to pyrroles. The products are smoothly obtained in moderate to good overall yields.

Key words

triphenyl phosphite - chlorine - pyrroles - allylamides - cyclizations

References

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9

While triphenyl phosphate originated as a by-product of the halogenation step, [6a] transesterification of triphenyl phosphate during the base-promoted cyclization would furnish phenol.