Catalytic C−C Bond Formation through Selective Activation of C−F Bonds

Regioselectivity in nickel(0)/phosphine catalyzed cycloadditions of alkynes and isocyanates

“…Ethyl isocyanate and phenyl isocyanate were purchased from Aldrich, dried and degassed prior to use. SIPr was prepared as previously reported [22]. All other reagents were purchased and used without further purification unless otherwise noted.…”

Transition metal catalyzed cross-coupling of aryl Grignard reagents with aryl fluorides via Pd- or Ni-activation of the C–F bond: an efficient synthesis of unsymmetrical biaryls – application of microwave technology in ligand and catalyst screening

“…Thus, effective catalyst systems were developed that furnished a variety of biaryl compounds under thermal or microwave conditions ( Table 3, entries [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. The cross-coupling could be performed with nickel or palladium catalyst systems using an assortment of aryl Grignard reagents (Table 3).…”

“…Kumada and co-workers [9] demonstrated for the first time a C-F activation process involving the reaction of fluorobenzene and i-PrMgCl mediated by NiCl 2 (dmpe) 2 . In a significant extension of this initial report, Herrmann and co-workers [10] expanded the use of aryl fluorides as synthetically useful substrates in these couplings by the application of N-heterocyclic carbenes as ligands in a nickel catalyzed cross-coupling with aryl Grignard reagents. Most recently, Mongin et al [11].…”

“…Efforts have been made to expand the synthetic scope of these coupling reactions to include aryl electrophiles such as benzonitriles [5], anisoles [6], and aryl carbamates [7], which were previously regarded as unreactive in these transition-metal cross-coupling procedures. Within the aryl halide series of compounds, aryl fluorides have been known to be the least reactive toward standard cross-coupling protocols [9][10][11][12][13]. Indeed, activation of a C-F bond is an extremely challenging process due to the inherent strength of this bond [8].…”

Efficient synthesis of triarylamines catalyzed by palladium/N-heterocyclic carbene

“…NHCs possess advantages of strongly -donating ability, air-and thermal stability, and easy tuning of steric and electronic properties as well as easy preparation. The nucleophilic NHCs as ancillary ligands found numerous applications in transition metal-catalyzed cross-coupling reactions [16][17][18][19][20][21][22]. In the utility of NHCs as ligands in catalyst systems for the C-N coupling processes, great advances have been made in very recent years.…”