Solid-state structure, solution-state behaviour and catalytic activity of electronically divergent C,N-chelating palladium-N-heterocyclic carbene complexesElectronic supplementary information (ESI) available. CCDC 1031837, 1405826-1405829 and 1405831-1405835. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c5dt02194d

A family of electronically diverse pyridyl- and picolyl-substituted imidazolium salts have been prepared and coordinated to palladium in a single step, to deliver a variety of palladium( ii )-N-heterocyclic carbene (NHC) complexes. Neutral Pd(NHC)X 2 , cationic [Pd(NHC) 2 X]X and dicationic [Pd(NHC) 2 ]X 2 -type complexes have been isolated and fully characterised, with single-crystal X-ray analysis revealing a variety of coordination environments around the palladium centres. The pre-formed complexes have been employed in a model Suzuki-Miyaura cross-coupling reaction to yield a sterically congested tetra- ortho -substituted biaryl product, showcasing turnover numbers comparable to Pd-PEPPSI-IPr catalyst. Electronically diverse pyridyl-substituted Pd( ii )-NHC complexes have been employed in Suzuki-Miyaura cross-coupling to yield a sterically congested tetra- ortho -substituted biaryl product.