18931-79-8Relevant academic research and scientific papers
Palladium-Catalyzed, ortho-Selective C-H Halogenation of Benzyl Nitriles, Aryl Weinreb Amides, and Anilides
Das, Riki,Kapur, Manmohan
, p. 1114 - 1126 (2018/06/18)
A palladium-catalyzed, ortho-selective C-H halogenation methodology is reported herein. The highlight of the work is the highly selective C(sp2)-H functionalization of benzyl nitriles in the presence of activated C(sp3)-H bond, which results in good yields of the halogenated products with excellent regioselectivity. Along with benzyl nitriles, aryl Weinreb amides and anilides have been evaluated for the transformation using aprotic conditions. Mechanistic studies yield interesting aspects with respect to the pathway of the reaction and the directing group abilities.
Palladium-catalyzed regio- and chemoselective direct desulfitative arylation of anilides with arylsulfonyl chlorides
Kianmehr, Ebrahim,Tanbakouchian, Arezoo
, p. 5337 - 5343 (2017/08/11)
A straightforward and practical palladium-catalyzed regioselective arylation of anilides is described. This method provides a new approach to prepare 2-aminobiaryls, which are valuable precursors for the synthesis of various N-containing heterocycles, using arylsulfonyl chlorides as readily available arylating agents.
Amide-assisted radical strategy: Metal-free direct fluorination of arenes in aqueous media
Liang, Deqiang,Li, Yanni,Gao, Shulin,Li, Renlun,Li, Xiangguang,Wang, Baoling,Yang, Hai
supporting information, p. 3344 - 3349 (2017/07/28)
A metal- and initiator-free direct fluorination of arenes with the assistance of an amide group is developed. This reaction proceeded under simple aqueous conditions with good functional group tolerance and ortho-para selectivity, and is highly practical because it could be readily scaled up to a multigram-scale. At this stage, an exclusive mechanism could not be proposed, and several possibilities have been discussed. The possibility of the amide-assisted radical chain mechanism has been supported by experimental and computational investigations as well as a seminal work.
Mild C - H halogenation of anilides and the isolation of an unusual palladium(I)-palladium(II) species
Bedford, Robin B.,Haddow, Mairi F.,Mitchell, Charlotte J.,Webster, Ruth L.
, p. 5524 - 5527 (2011/07/31)
Reducing the load: A facile palladium-catalyzed ortho-selective bromination and chlorination of anilides occurs under aerobic conditions at room temperature when N-halosuccinimides (NXS) are used in the presence of p-toluenesulfonic acid (PTSA). The orthopalladated PTSA complex is not only catalytically competent but also undergoes a reductive process to yield an unusual PdI-PdII tetramer (see structure; Pdgreen, Ored, Syellow, Cgray). Copyright
Solvent-free aromatic C-H functionalisation/halogenation reactions
Bedford, Robin B.,Engelhart, Jens U.,Haddow, Mairi F.,Mitchell, Charlotte J.,Webster, Ruth L.
supporting information; experimental part, p. 10464 - 10472 (2011/01/05)
The solvent-free, palladium-catalysed reaction of anilides with CuCl 2 in the presence or absence of copper acetate yields ortho-chlorinated anilides in good to excellent yields, even on a large scale (100 mmol). By contrast, the equivalent reactions with copper bromide, either solvent free or in 1,2-dichloroethane, in the presence or absence of palladium, under air or inert conditions, gave the products of simple electrophilic bromination. Mechanistic studies highlighted the involvement of palladacyclic intermediates, one of which was characterised crystallographically, which undergo subsequent reaction with copper(ii) chloride to yield the chlorinated anilide products.
