Application of in situ-generated Rh-bound trimethylenemethane variants to the synthesis of 3,4-fused pyrroles.

Rh-bound trimethylenemethane variants generated from the interaction of a Rh-carbenoid with an allene have been applied to the synthesis of substituted 3,4-fused pyrroles. The pyrrole products are useful starting points for the syntheses of various dipyrromethene ligands. Furthermore, the methodology has been applied to a synthesis of the natural product cycloprodigiosin, which demonstrates antitumor and immunosuppressor activity.