4096-20-2Relevant articles and documents
Palladium-catalyzed synthesis of arylamines from diphenyliodonium tetrafluoroborate and secondary amine
Kang, Suk-Ku,Lee, Hong-Woo,Choi, Won-Kyu,Hong, Ryung-Kee,Kim, Jae-Sun
, p. 4219 - 4224 (1996)
The hetero-cross coupling reaction of diphenyliodonium tetrafluoroborate with secondary amine in the presence of LiNTMS2 or NaOtBu as base, Pd2(dba)3?CHCl3 as catalyst, and tri-o-tolylphosphine as ligand afforded arylamines at room temperature under mild conditions.
Phosphines with N-Heterocyclic Boryl-Substituents: Ligands for Coordination Chemistry and Catalysis
Kaaz, Manuel,Locke, Ralf J. C.,Merz, Luisa,Benedikter, Mathis,K?nig, Simon,Bender, Johannes,Schlindwein, Simon H.,Nieger, Martin,Gudat, Dietrich
, p. 1586 - 1593 (2019)
Boryl-substituted phosphines NHB–P(R)Ph (R = H, Ph, NHB = N-heterocyclic boryl substituent) react with Fe2(CO)9 to give isolable Fe(CO)4 complexes, two of which were characterized by single-crystal XRD studies. The electronic and steric properties for a series of the boryl phosphines were further assessed by evaluation of TEPs for in-situ formed complexes [RhCl(NHB–PR1R2)(CO)2] (R1, R2 = H, Ph, Me, NMe2), and calculations of buried volumes for Fe(CO)4 complexes. The results imply that the NHB-phosphines exhibit due to their conformational flexibility some variability in their steric bulk, and that some specimens may exhibit similar electron releasing power and steric demand as tBu3P. Studies of the amination of bromobenzene with 2,6-diisopropylaniline confirmed that these properties can be exploited to promote Pd-catalyzed C–N cross coupling reactions, and that formal replacement of a phenyl by a NHB substituent in the auxiliary phosphine has a beneficial effect on catalyst performance.
Synthesis, characterisation and reactivity of copper(I) amide complexes and studies on their role in the modified Ullmann amination reaction
Sung, Simon,Braddock, D. Christopher,Armstrong, Alan,Brennan, Colin,Sale, David,White, Andrew J.P.,Davies, Robert P.
, p. 7179 - 7192 (2015)
A series of copper(I) alkylamide complexes have been synthesised; copper(I) dicyclohexylamide (1), copper(I) 2,2,6,6-tetramethylpiperidide (2), copper(I) pyrrolidide (3), copper(I) piperidide (4), and copper(I) benzylamide (5). Their solid-state structures and structures in [D6]benzene solution are characterised, with the aggregation state in solution determined by a combination of DOSY NMR spectroscopy and DFT calculations. Complexes 1, 2 and 4 are shown to exist as tetramers in the solid state by X-ray crystallography. In [D6]benzene solution, complexes 1, 2 and 5 were found by using 1H DOSY NMR to exist in rapid equilibrium between aggregates with average aggregation numbers of 2.5, 2.4 and 3.3, respectively, at 0.05 M concentration. Conversely, distinct trimeric, tetrameric and pentameric forms of 3 and 4 were distinguishable by one-dimensional 1H and 1H DOSY NMR spectroscopy. Complexes 3-5 are found to react stoichiometrically with iodobenzene, in the presence or absence of 1,10-phenanthroline as an ancillary ligand, to give arylamine products indicative of their role as potential intermediates in the modified Ullmann reaction. The role of phenanthroline has also been explored both in the stoichiometric reaction and in the catalytic Ullmann protocol.
Iridium and bis(4-nitrophenyl)phosphoric acid catalysed amination of diol by hydrogen-borrowing methodology for the synthesis of cyclic amine: Synthesis of clopidogrel
Swain, Sharada Prasanna,Shri, Om,Ravichandiran
, (2021/05/13)
The borrowing hydrogen method is an environmentally benign process for the synthesis of amines, as H2O is the side product. A new green process for the amination of diol by [Ir] catalyst 15 and bis(4-nitrophenyl)phosphoric acid for the synthesis of cyclic amine is reported. This method was successfully applied for the synthesis of antiplatelet drug clopidogrel.
Mediator-Enabled Electrocatalysis with Ligandless Copper for Anaerobic Chan-Lam Coupling Reactions
Walker, Benjamin R.,Manabe, Shuhei,Brusoe, Andrew T.,Sevov, Christo S.
supporting information, p. 6257 - 6265 (2021/05/07)
Simple copper salts serve as catalysts to effect C-X bond-forming reactions in some of the most utilized transformations in synthesis, including the oxidative coupling of aryl boronic acids and amines. However, these Chan-Lam coupling reactions have historically relied on chemical oxidants that limit their applicability beyond small-scale synthesis. Despite the success of replacing strong chemical oxidants with electrochemistry for a variety of metal-catalyzed processes, electrooxidative reactions with ligandless copper catalysts are plagued by slow electron-transfer kinetics, irreversible copper plating, and competitive substrate oxidation. Herein, we report the implementation of substoichiometric quantities of redox mediators to address limitations to Cu-catalyzed electrosynthesis. Mechanistic studies reveal that mediators serve multiple roles by (i) rapidly oxidizing low-valent Cu intermediates, (ii) stripping Cu metal from the cathode to regenerate the catalyst and reveal the active Pt surface for proton reduction, and (iii) providing anodic overcharge protection to prevent substrate oxidation. This strategy is applied to Chan-Lam coupling of aryl-, heteroaryl-, and alkylamines with arylboronic acids in the absence of chemical oxidants. Couplings under these electrochemical conditions occur with higher yields and shorter reaction times than conventional reactions in air and provide complementary substrate reactivity.
Iodine-Mediated Coupling of Cyclic Amines with Sulfonyl Hydrazides: an Efficient Synthesis of Vinyl Sulfone Derivatives
Rong, Xiaona,Guo, Jingwen,Hu, Zheqi,Huang, Lehao,Gu, Yugui,Cai, Yuepiao,Liang, Guang,Xia, Qinqin
supporting information, p. 701 - 708 (2020/12/30)
An efficient iodine-mediated coupling of cyclic amines with sulfonyl hydrazides is reported. This transformation opens a new route to the synthesis of vinyl sulfones derivatives, which is a common structural motif in natural products and pharmaceuticals. Tentative mechanistic studies suggest that this reaction is likely to involve a radical process.
