作者:Andrey Borzenko、Nicolas L. Rotta-Loria、Preston M. MacQueen、Christopher M. Lavoie、Robert McDonald、Mark Stradiotto
DOI:10.1002/anie.201410875
日期:2015.3.16
diverse (hetero)aryl chloride, bromide, and tosylate electrophiles were employed in the Ni‐catalyzed monoarylation of ammonia, including chemoselective transformations. The employed JosiPhos/[Ni(cod)2] catalyst system enables the use of commercially available stock solutions of ammonia, or the use of ammonia gas in these reactions, thereby demonstrating the versatility and potential scalability of the reported
We report herein a facile synthetic method for converting unactivated (hetero)aryl electrophiles into β-fluoroethylated (hetero)arenes via nickel-catalyzed reductive cross-couplings. This coupling reaction features the involvement of FCH2 CH2 radical intermediate rather than β-fluoroethyl manganese species which provides effective solutions to the problematic β-fluoride side eliminations. The practical
The present invention provides an activator in arylamination using a palladium compound as a catalyst, which is superior to conventional phosphines in stability and performance. With the phosphine sulfide as an activator, an arylamination reaction achieves improved selectivity to produce a desired aromatic amine in an obviously increased yield as compared with a reaction using the corresponding phosphine compound. Moreover, the phosphine sulfide of the invention is impervious to oxidation and exists stably in air and therefore sufficiently withstands use on an industrial scale.
Methyl- and ethyl arylcarboxylates were synthesized by palladium-catalyzed alkoxycarbonylation of various aryl p-toluenesulfonates (tosylates). Yields were highly dependent on the substituent of aryl tosylates and phosphine ligands used. Ethoxycarbonylation of 4-acetylphenyl tosylate by the use of a bisphosphine ligand gave ethyl 4-acetylbenzoate in quite satisfactory yields.
Cross-Coupling of Phenol Derivatives with Umpolung Aldehydes Catalyzed by Nickel
作者:Leiyang Lv、Dianhu Zhu、Jianting Tang、Zihang Qiu、Chen-Chen Li、Jian Gao、Chao-Jun Li
DOI:10.1021/acscatal.8b01224
日期:2018.5.4
cross-coupling to construct the C(sp2)–C(sp3) bond was developed from two sustainable biomass-based feedstocks: phenolderivatives with umpolung aldehydes. This strategy features the in situ generation of moisture/air-stable hydrazones from naturally abundant aldehydes, which act as alkyl nucleophiles under catalysis to couple with readily available phenolderivatives. The avoidance of using both halides