Efficient Heck reactions catalyzed by a palladium/diol–imidazolium salt in aerial atmosphere

α, β-Alkynone Accelerated PPM Level Pd-Catalyzed Sonogashira Coupling Reaction

“…Interestingly, N-phenylurea, thiourea, and amide efficiently accelerated the 1-100 ppm, Pd-catalyzed Suzuki reaction (Scheme 1d) [10]. Although these new ligands have a significant role in the trace palladium-catalyzed coupling reactions, most phosphine ligands are expensive, highly toxic, and sensitive to air and water [11][12][13]. More importantly, the strong coordination of these ligands with Pd may completely deactivate the catalyst at ppm levels.…”

Iron-Catalysed Mizoroki–Heck Reaction using 2,2′-Diamino-6,6′-Dimethylbiphenyl as the Ligand

“…[11][12][13][14] Because of the high cost of palladium salts and the air-sensitivity and toxicity of phosphine-based ligands, alternative metals as well as ligands have been developed. [15][16][17][18][19][20][21][22][23][24][25] In the past few years, iron salts, as one of the most inexpensive and environmentally friendly salts on the earth, have been proved to be efficient catalysts for carbon-carbon and carbon-heteroatom bond formation. [26][27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42][43] Recently, Shao, Lu and co-workers found that 2,2p-diamino-6,6p-dimethylbiphenyl (L), as a non-phosphine compound, is a good ligand in the transition metal catalysed carbon-carbon bond formation reactions.…”

Revisiting Heck–Mizoroki reactions in ionic liquids

“…However, attempts to use the electro-deficient p-chloronitrobenzene were not well succeeded. Soon afterwards the same group 95 reported the synthesis of another diol based on imidazole, the 1-(2,3-dihydroxypropyl)-3-methylimidazolium hexafluorophosphate (49) (Fig. 9).…”