101293-08-7Relevant articles and documents
Polymer-supported copper complex for C-N and C-O cross-coupling reactions with aryl boronic acids
Chiang, Gary C. H.,Olsson, Thomas
, p. 3079 - 3082 (2004)
(Chemical Equation Presented) Immobilization of copper onto modified Wang resin provided a polymer-supported copper catalyst, which is effective in cross-coupling reactions between N- or O-containing substrates and arylboronic acids. The copper catalyst is air stable and can be recycled with minimal loss of activity.
Copper-catalyzed coupling of arylboronic acids and amines.
Antilla,Buchwald
, p. 2077 - 2079 (2001)
[reaction: see text] A general catalytic coupling of arylboronic acids and amines is reported. This room-temperature coupling was realized through the use of catalytic copper(II) acetate, 2,6-lutidine as base, and myristic acid as an additive. Functionalized aniline substrates provided the diarylamine coupling products in good yield (58-91%). A variety of alkylamines were also successfully coupled to give N-alkyl anilines in moderate yield (50-64%).
NaBHT Generated in Situ from BHT and NaO tBu: Crystallographic Characterization and Applications in Buchwald-Hartwig Amination
Semeniuchenko, Volodymyr,Ovens, Jeffrey S.,Braje, Wilfried M.,Organ, Michael G.
, p. 3276 - 3290 (2021/10/12)
NaBHT is a valuable medium-strength base useful for many applications, particularly for Buchwald-Hartwig coupling. The structures of solvent-free NaBHT and its solvates with Et2O, THF, tBuOH, and a THF/tBuOH mixture were established using single-crystal X-ray diffraction. While [NaBHT·Et2O]2 adopts a dimeric structure and crystallizes in a monoclinic cell, [NaBHT·THF]3, [NaBHT·tBuOH]3, and [NaBHT·(THF-tBuOH)]3 prefer a trimeric structure and crystallize in cubic cells. Solvent-free [NaBHT]n is different from solvated NaBHT and from other known sodium phenolates. It is an inorganic polymer that crystallizes in an orthorhombic cell, with a NaO core spreading in the [1 0 0] direction. Agostic interactions of the tBu group hydrogens with Na, which were confirmed for all structures, may help explain the reductive properties of NaBHT. Further, interactions of BHT with tBuONa in solution and in the solid state were examined, reveraling that NaBHT does not need to be prepared from pyrophoric NaH or metallic Na every time. Instead, it can be generated efficiently in or ex situ using NaOtBu in solution or with only a stoichiometric amount of solvent to assist in bringing the reactants together. Application of this methodology was demonstrated with the efficient, solvent-free, and Pd-catalyzed C-N coupling with Pd(NHC) catalysts.
Well-Designed N-Heterocyclic Carbene Ligands for Palladium-Catalyzed Denitrative C-N Coupling of Nitroarenes with Amines
Chen, Kai,Chen, Wanzhi,Chen, Wei,Liu, Miaochang,Wu, Huayue
, p. 8110 - 8115 (2019/08/26)
The C-N bond formation is one of the fundamental reactions in organic chemistry, because of the widespread presence of amine moieties in pharmaceuticals and biologically active compounds. Palladium-catalyzed C-N coupling of haloarenes represents one of the most efficient approaches to aromatic amines. Nitroarenes are ideal alternative electrophilic coupling partners, since they are inexpensive and readily available. The denitration and cross-coupling using nitroarenes as the electrophilic partners is challenging, because of the low reactivity of the Ar-NO2 bond toward oxidative addition. We report here the C-N coupling of nitroarenes and amines using palladium/5-(2,4,6-triisopropylphenyl)imidazolylidene[1,5-a]pyridines as the catalyst. The ligands are readily available from commercial chemicals. The reaction shows broad substrate scope and functional group tolerance. The method is applicable to both aromatic and aliphatic amines, and many secondary and tertiary aromatic amines bearing various functional groups were obtained in high yields.
Cu-Catalyzed Aerobic Oxidative N-N Coupling of Carbazoles and Diarylamines Including Selective Cross-Coupling
Ryan, Michael C.,Martinelli, Joseph R.,Stahl, Shannon S.
supporting information, p. 9074 - 9077 (2018/07/21)
A Cu-catalyzed method has been identified for aerobic oxidative dimerization of carbazoles and diarylamines to the corresponding N-N coupled bicarbazoles and tetraarylhydrazines. The reactions proceed under mild conditions (1 atm O2, 60-80 °C)
Base-assisted, copper-catalyzed N-arylation of (benz)imidazoles and amines with diarylborinic acids
Guan, Changwei,Feng, Yuanyuan,Zou, Gang,Tang, Jie
, p. 6906 - 6913 (2017/11/03)
N-Arylation of (benz)imidazoles and amines with diarylborinic acids as cost-effective aryl source has been efficiently effected via Cu(OAc)2-catalyzed Chan-Lam coupling in assistance of tetramethylethylenediamine (TMEDA) in methanol and pyridine (Py) in dichloromethane, respectively, in air at room temperature. The diarylborinic acids could be well accommodated by the Chan-Lam coupling oxidative conditions containing a proper combination of bases and solvents. The steric hindrance appeared to affect the copper-catalyzed N-arylation using the high-order arylboron reagent more significantly than the electronic factors, especially for low reactive anilines and aliphatic amines.
Selective Monoarylation of Primary Anilines Catalyzed by Pd(dippf) and its Application in OLED Component Synthesis
Grünberg, Matthias F.,Jia, Fan,Rivas-Nass, Andreas,Goo?en, Lukas J.
supporting information, p. 1589 - 1594 (2016/10/13)
Palladium 1,1′-bis(diisopropylphosphino)-ferrocene [Pd(dippf)] complexes were found to promote the monoarylation of primary anilines with unprecedented selectivities. They also allow the sequential arylation of primary anilines with two different aryl bromides in one pot. The reactions can be performed at low catalyst loadings (0.2 mol%) and high substrate concentrations. The synthetic utility of the optimum catalyst was demonstrated by the synthesis of various di- and triarylamines. A particular focus was set on compounds with carbazole and fluorene moieties as employed in state-of-the-art small-molecule organic light emitting diodes (OLEDs). (Figure presented.).
Palladium-catalyzed aerobic dehydrogenative aromatization of cyclohexanone imines to arylamines
Hajra, Alakananda,Wei, Ye,Yoshikai, Naohiko
supporting information, p. 5488 - 5491,4 (2012/12/12)
Dehydrogenative aromatization of cyclohexanone imines to arylamines has been achieved using a palladium catalyst under aerobic conditions. The reaction is applicable to a variety of imines that are either preformed or generated in situ from cyclohexanone derivatives and aryl or alkylamines.
Inverse Triphenylmethylium Dyes
Hellwinkel, Dieter,Gaa, Heinrich Georg,Gottfried, Reiner
, p. 1045 - 1060 (2007/10/02)
When in the conventional triphenymethylium dye systems of the crystal violet and malachit green type, 6 and 7, the N-donor and C(+)-acceptor centers are interchanged, the "Inverse Triphenylmethylium Dye Types" 4 and 5 are obtained, showing very similar colors.The stable models with R = phenyl (8 - 10) and R = p-tolyl (11 - 13) were investigated in more detail.The visual observations were supported by the VIS spectra which showed nearly the same longest wavelength absorption maxima for corresponding pairs of inverse and conventional dye representatives.The experimental results can be interpreted with a simple HMO-model according to which the longest wavelength absorptions correspond here to transitions of equal energy from weakly bonding to nonbonding and from nonbonding to weakly antibonding molecular orbitals, respectively.On the same basis numerous isoelectronic variants of that dye type can be envisaged.In the NMR-spectra of the new dyes, characteristically increasing deshieldings of nearly all positions are observed in going from the mono- (10(+), 13(+)) through the di- (9(++), 12(++)) to the trications (8(+++), 11(+++)). - Key words: Dyes, Di-, Tricarbeniumions, NMR Spectra, VIS Spectra
