Synthesis of [N,P] ligands based on pyrrole. Application to the total synthesis of arnottin I

This paper describes the synthesis of a new class of [N,P] ligands based on pyrrole with a dimethylamino group as hard donor and a phosphine moiety as soft base. We have also modified the phosphine fragment to change the electronic and steric properties of these ligands. Palladium complex 3a proved to be very efficient in Heck cross-coupling reactions and in intramolecular aryl–aryl couplings of esters and amides. We have demonstrated the applicability and efficiency of this novel catalyst in the total synthesis of the natural product arnottin I.