Palladium-catalyzed C-C and C-heteroatom cross-coupling reactions 1 remain some of the most widely used methods in pharmaceutical, 2 agrochemical, 3 natural product, and materials synthesis. The common first step in this family of reactions occurs by oxidative addition of an organic electrophile to Pd(0) leading to the formation of organo-Pd(II) intermediates of general structure LnPd(R)X (Figure ). These so-called palladium oxidative addition complexes (OACs) have long been valuable species in mechanistic studies of cross-coupling reactions. Their potential utility as stoichiometric reagents for challenging late-stage functionalization reactions 8 and particularly as state-of-the-art catalysts in a variety of coupling reactions has emerged more recently. A key attribute of palladium OACs is they are on-cycle catalytic intermediates and consequently are decoupled from complications associated with catalyst initiation. 10 Other contemporary Pd precatalysts, such as palladacycles, 11 (π-allyl)Pd complexes, or Pd(I) dimers must first transform into the Pd(0) active species prior to catalysis, each requiring certain reagents or conditions to occur smoothly. Likewise, isolable Pd(0) complexes, such as Pd2dba3 and [Pd2(PR3)2(µ-COD)] precatalysts 9a,14 or more the recently developed complexes Pd( DMP DAB)(MAH) or Pd(COD)(DQ) are subject to complications from competitive binding of residual π-acid or chelating alkenes to the active Pd(0) species. In this regard, Pd OACs could be regarded as ideal catalysts, but their broader option in catalysis has to date been throttled by limited accessibility.