1186195-11-8Relevant articles and documents
Direct Difluoromethylation of Aryl Halides via Base Metal Catalysis at Room Temperature
Xu, Long,Vicic, David A.
, p. 2536 - 2539 (2016)
A stable and isolable difluoromethyl zinc reagent has been prepared through the reaction of ICF2H with diethyl zinc and DMPU. This new zinc reagent is a free-flowing solid and can be used in combination with a nickel catalyst to difluoromethylate aryl iodides, bromides, and triflates at room temperature. Such mild conditions for the catalytic difluoromethylation of these substrates are unprecedented.
Two Ligands Transfer from Ag to Pd: En Route to (SIPr)Pd(CF2H)(X) and Its Application in One-Pot C-H Borylation/Difluoromethylation
Herbert, Simon,Kinzel, Tom,Shen, Qilong,Zhang, Wei,Zhao, Haiwei
, p. 3596 - 3604 (2020/03/23)
A process for the concurrent transfer of both the NHC ligand and the difluoromethyl group from [(SIPr)Ag(CF2H)] to PdX2 (X = Cl, OAc, and OPiv) for the preparation of [(SIPr)Pd(CF2H)X] complexes is described. These complexes were air-stable and easily underwent transmetalation with aryl pinacol boronate/reductive elimination to generate ArCF2H in high yields. Based on this discovery, the first one-pot C-H borylation and difluoromethylation process for the preparation of difluoromethylated (hetero)arenes was developed.
Precatalyst Effects on Pd-Catalyzed Cross-Coupling Difluoromethylation of Aryl Boronic Acids
Hori, Kaishi,Motohashi, Hirotaka,Saito, Daichi,Mikami, Koichi
, p. 417 - 421 (2019/01/11)
The Pd-catalyzed difluoromethylation of aryl boronic acids with difluoroiodomethane is shown to provide the difluoromethyl compounds in high to moderate yields by Pd(PPh3)2/DPEphos catalyst in H2O/toluene. Mechanistic studies show that the oxidative addition by Pd(PPh3)4 rather than Pd2(dba)3 precatalyst to difluoroiodomethane provides a square-planar trans-(PPh3)2Pd(II)(CF2H)I complex defined by X-ray crystallographic analysis. The trans-(PPh3)2Pd(CF2H)I complex is transformed to cis-(PPh3)2Pd(CF2H)Ph detected by low temperature NMR analysis, via transmetalation with phenylboronic acids. The reductive elimination occurs via ligand exchange to DPEphosPd(CF2H)Ph to give Ph-CF2H (t1/2 = 144.7 min at 20 °C) with formation of the Pd(0)(PPh3)2/DPEphos catalyst.
Metallaphotoredox Difluoromethylation of Aryl Bromides
Bacauanu, Vlad,Cardinal, Sébastien,Yamauchi, Motoshi,Kondo, Masaru,Fernández, David F.,Remy, Richard,MacMillan, David W. C.
supporting information, p. 12543 - 12548 (2018/09/18)
Herein, we report a convenient and broadly applicable strategy for the difluoromethylation of aryl bromides by metallaphotoredox catalysis. Bromodifluoromethane, a simple and commercially available alkyl halide, is harnessed as an effective source of difluoromethyl radical by silyl-radical-mediated halogen abstraction. The merger of this fluoroalkyl electrophile activation pathway with a dual nickel/photoredox catalytic platform enables the difluoromethylation of a diverse array of aryl and heteroaryl bromides under mild conditions. The utility of this procedure is showcased in the late-stage functionalization of several drug analogues.
