Diazadienes as control ligands in homogeneous catalysis XVIII. Palladacyclopentadienes and platinacyclopentadienes and the co-cyclotrimerization of various alkynes
Bis(dibenzylidene acetone)palladium reacts readily with N-aryl diazadienes (dad = ArN=CRCR=NAr) and two moles of dialkyl acetylenedicarboxylates ECCE (E = COOR) to form the palladacyclopentadienes (dad)PdCE=CECE=CE (2a-h).With a propiolic ester HCCE