N-Heterocyclic carbenes (NHCs) have been known to be efficient ligands for the Suzuki–Miyaura cross-coupling. In this work, four novel 2-methyl-2-propenyl substituted N-heterocyclic carbene ligands (1a-d) were synthesized and they were used to produce four novel air-stable PEPPSI-type palladium–NHC complexes (2a-d). All of the new compounds were fully characterized by elemental analysis, 1H, 13C NMR and FT-IR spectroscopies. In addition, prepared complexes (2a-d) were investigated as catalysts in the Suzuki–Miyaura coupling reaction under very mild conditions using a mixture of i-PrOH/water as a solvent and a base at the room temperature. Under optimal reaction conditions, the expected biaryl products were obtained in moderate to high yields.