122-39-4Relevant articles and documents
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Hirsch
, p. 1973 (1892)
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A practical removal method of camphorsultam
Hasegawa, Tomoyuki,Yamamoto, Hisashi
, p. 882 - 884 (1998)
A mild and efficient removal of camphorsultam was realized using tetrabutylammonium hydrogen peroxide as a key reagent.
PHOTOCHEMISTRY OF 1,3-DIPHENYLTRIAZENE IN VARIOUS MEDIA. II: SOLID STATE PHOTOLYSIS.
Baro,Dudek,Luther,Troe
, p. 1161 - 1164 (1983)
Solid 1,3-diphenyltriazene (DPT) has been photolyzed at 290 nm and 360 nm. The distribution of the photoproducts showed that recombination of the radicals produced after photochemical excitation was governed by a 'cage effect' favoring a minimum of motion of the recombining radicals. In many details the results differ from observations on the photochemistry of DPT in liquid solutions. The photolysis of DPT in polymethylmethacrylate films, however, resembles the photochemistry of DPT in liquid solutions.
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Koga,Anselme
, p. 446 (1968)
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Palladium-Imidazolium N-Heterocyclic Carbene-Catalyzed Carbonylative Amidation with Boronic Acids, Aryl Diazonium Ions, and Ammonia
Ma, Yudao,Song, Chun,Chai, Qiang,Ma, Changqin,Andrus, Merritt B.
, p. 2886 - 2889 (2003)
Aryl diazonium tetrafluoroborates have been coupled with arylboron compounds, carbon monoxide, and ammonia to give aryl amides in high yields. A saturated N-heterocyclic carbene (NHC) ligand, H2IPr was used with palladium(II) acetate to give the active catalyst. A mechanism is proposed for this novel four-component coupling reaction.
KINETICS OF REACTIONS IN THE THERMAL DECOMPOSITION OF TETRAPHENYLHYDRAZINE IN THE PRESENCE OF A MIXTURE OF STERICALLY HINDERED PHENOL AND HYDROPEROXIDE
Varlamov, V. T.,Denisov, E. T.
, p. 2211 - 2215 (1986)
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Reactions of nitrenium ions with arenes: Laser flash photoylsis detection of a σ-complex between N,N-diphenylnitrenium ion and alkoxybenzenes [1]
McIlroy,Falvey
, p. 11329 - 11330 (2001)
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Reductive Phenylation of Nitroarenes
Ohta, Toshiharu,Machida, Ryosuke,Takeda, Kei,Endo, Yasuyuki,Shudo, Koichi,Okamoto, Toshihiko
, p. 6385 - 6386 (1980)
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Nickel(II) thiolates derived from transmetallation reaction of [Zn(Tab)4](PF6)2 with Ni(II) ions and their catalytic activity toward the CN coupling reactions
Shi, Jing,Li, Fu-Ling,Li, Hong-Xi,Wang, Fan,Yu, Hong,Ren, Zhi-Gang,Zhang, Wen-Hua,Lang, Jian-Ping
, p. 159 - 162 (2014)
Reactions of NiCl2·6H2O or Ni(ClO 4)2·6H2O with 2,2′-bipyridine (2,2′-bipy), or 2-bis(diphenylphosphino)ethane (dppe) or 1,4-bis(diphenylphosphino)butane (dppb) followed by addition of [Zn(Tab) 4](PF6)2 (1) resulted in the formation of one trinuclear cationic complex [(2,2′-bipy)4Ni3(μ- Tab)4]Cl0.5(PF6)5.5 (2), one mononuclear cationic complex [Ni(Tab)2(dppe)](PF6) 2 (3), and one dinuclear cationic complex [Ni2(dppb)(μ- Tab)2(Tab)2](PF6)2(ClO 4)2 (4). Complexes 2-4 were characterized by elemental analysis, IR, UV-vis, 1H and 31P NMR, and single-crystal X-ray diffraction. In the [(2,2′-bipy)4Ni3(μ-Tab) 4]6 + hexacation of 2, the central Ni(II) atom is connected to two [Ni(2,2′-bipy)2]2 + fragments by two pairs of μ-Tab ligands, forming a linear trinuclear cationic structure. The Ni(II) center of the dication of 3 is tetrahedrally coordinated by two S atoms from two Tab ligands and two P atoms of one dppe ligand. Complex 4 has a dimeric cationic structure in which two [(Tab)Ni]2 + species are linked by a pair of μ-Tab ligands and one dppb ligand. Complexes 2-4 displayed high catalytic activity toward the cross-coupling reactions of arylboronic acids and amines to produce N-arylated amines.
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Hodgson,Marsden
, (1939)
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Reduction of N-nitrosodiphenylamine to the corresponding hydrazine by guinea pig liver preparations
Tatsumi,Yamada
, p. 3842 - 3845 (1982)
The present study provides first evidence for enzymatic reduction of a noncyclic nitrosamine to the corresponding hydrazine. Under anaerobic conditions, N-nitrosodiphenylamine was reduced to 1,1-diphenylhydrazine by guinea pig liver 9,000 xg supernatant or cytosol in the presence of an NADPH-generating system and FAD, or NADH and FAD. However, guinea pig liver microsomes did not catalyze the reduction of the nitrosamine at all. The reduction product was isolated from the reaction mixture and identified unequivocally by comparing with authentic samples its mass and UV spectra, and its behavior in HPLC and TLC. Under aerobic conditions, no formation of the hydrazine was observed by HPLC and TLC examinations. However, when aerobic incubation was performed in the presence of acetaldehyde, a reduction product was isolated and identified as the acetaldehyde hydrazone derivative.
Selective palladium-catalyzed arylation of ammonia: Synthesis of anilines as well as symmetrical and unsymmetrical di- and triarylamines
Surry, David S.,Buchwald, Stephen L.
, p. 10354 - 10355 (2007)
It is shown that by selection of an appropriate palladium/ligand system, temperature, concentration, and stoichiometry of reagents, ammonia may be selectively arylated to give either anilines, symmetrical di-, or triarylamines. Furthermore different aryl halides may be added sequentially to the reaction mixture, allowing the synthesis of unsymmetrical di- and triarylamines from aryl halides and ammonia in a one-pot protocol Copyright
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Haberfield,Seif
, p. 1508 (1969)
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Oxidation of Diphenylamine by OH Radicals and Excitation of the Diphenylamino and OH Adduct Radicals
Schmidt, K. H.,Bromberg, A.,Meisel, Dan
, p. 4352 - 4357 (1985)
The primary product of the OH reaction with diphenylamine (DPAH) is a mixture of OH adducts (DPAH radical-OH) which subsequently eliminate OH- ions via a pH-independent and an acid-catalyzed process.The rate constants of these two processes have been determined.The acidic amino radical cation (DPAH+ radical) thus obtained has a pKa of 4.2.The adduct, the amino radical cation, and the neutral amino radical (DPA radical) were excited with frequency-doubled ruby laser pulses (347 nm).The excited state of the latter two amino radicals are shorter lived than the presently utilized laser pulse.Furthermore, no laser-induced shift in the acid-base equilibrium of DPAH+ radical/DPA radical could be observed.This lack of laser excitation effect leads to the conclusion that the difference in acid-base equilibrium constants (ΔpKa*) of the ground vs. the excited state is substantially smaller in the radical than in the analogous singlet states of the parent amine molecule.Foerster cycle considerations based on the absorption spectra of the two forms of the radical substantiate this conclusion.Excitation of the OH adduct leads to OH(1-) elimination from the excited state.This elimination leads to production of the amino radical cation in its ground state.Relaxation of this laser-induced perturbation of the acid-base equilibrium to its thermal value provides an independent method to measure the rates of equilibration.
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Hoelscher,Chamberlain
, p. 1558,1561 (1950)
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Vermillion,Rainsford,Hauser
, p. 68,72 (1940)
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Potassium tert-butoxide-mediated generation of arynes from o-bromoacetophenone derivatives
Chang, Denghu,Gao, Fei,Shi, Lei
, p. 2428 - 2434 (2018)
o-bromoacetophenone derivatives as new versatile aryne precursors are induced to selectively eliminate the CAr–Br and CAr–C(Ac) bonds in the help of t-BuOK. Furthermore, the active aryne intermediates are successfully appl
The Quest for the Ideal Base: Rational Design of a Nickel Precatalyst Enables Mild, Homogeneous C-N Cross-Coupling
Liu, Richard Y.,Dennis, Joseph M.,Buchwald, Stephen L.
, p. 4500 - 4507 (2020)
Palladium-catalyzed amination reactions using soluble organic bases have provided a solution to the many issues associated with heterogeneous reaction conditions. Still, homogeneous C-N cross-coupling approaches cannot yet employ bases as weak and economical as trialkylamines. Furthermore, organic base-mediated methods have not been developed for Ni(0/II) catalysis, despite some advantages of such systems over those employing Pd-based catalysts. We designed a new air-stable and easily prepared Ni(II) precatalyst bearing an electron-deficient bidentate phosphine ligand that enables the cross-coupling of aryl triflates with aryl amines using triethylamine (TEA) as base. The method is tolerant of sterically congested coupling partners, as well as those bearing base- and nucleophile-sensitive functional groups. With the aid of density functional theory (DFT) calculations, we determined that the electron-deficient auxiliary ligands decrease both the pKa of the Ni-bound amine and the barrier to reductive elimination from the resultant Ni(II)-amido complex. Moreover, we determined that the preclusion of Lewis acid-base complexation between the Ni catalyst and the base, due to steric factors, is important for avoiding catalyst inhibition.
Probing Hydrogen Atom Transfer at a Phosphorus(V) Oxide Bond Using a "bulky Hydrogen Atom" Surrogate: Analogies to PCET
Chu, Jiaxiang,Carroll, Timothy G.,Wu, Guang,Telser, Joshua,Dobrovetsky, Roman,Ménard, Gabriel
, p. 15375 - 15383 (2018)
Recent computational studies suggest that the phosphate support in the commercial vanadium phosphate oxide (VPO) catalyst may play a critical role in initiating butane C-H bond activation through a mechanism termed reduction-coupled oxo activation (ROA) similar to proton-coupled electron transfer (PCET); however, no experimental evidence exists to support this mechanism. Herein, we present molecular model compounds, (Ph2N)3V=N-P(O)Ar2 (Ar = C6F5 (2a), Ph (2b)), which are reactive to both weak H atom donors and a Me3Si? (a "bulky hydrogen atom" surrogate) donor, 1,4-bis(trimethylsilyl)pyrazine. While the former reaction led to product decomposition, the latter resulted in the isolation of the reduced, silylated complexes (Ph2N)3V-N=P(OSiMe3)Ar2 (3a/b). Detailed analyses of possible reaction pathways, involving the isolation and full characterization of potential stepwise square-scheme intermediates, as well as the determination of minimum experimentally and computationally derived thermochemical values, are described. We find that stepwise electron transfer (ET) + silylium transfer (ST) or concerted EST mechanisms are most likely. This study provides the first experimental evidence supporting a ROA mechanism and may inform future studies in homogeneous or heterogeneous C-H activation chemistry, as well as open up a possible new avenue for main group/transition metal cooperative redox reactivity.
Scalable production of Cu@C composites for cross-coupling catalysis
Bu, Lijuan,Ming, Hai
, p. 163 - 166 (2015)
A novel Cu@C core-shell microstructure was prepared by reduction of [Cu(NH3)4]2+ with glucose using a mild hydrothermal process. The carbon shell of such Cu@C composite can be tuned to different carbonization degrees just through varying the calcination conditions. The structural properties of as-prepared Cu@C were investigated in detail by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), transmission electron micrographs (TEM) and Raman spectra. In addition, these Cu@C composites were firstly used to catalyze the CN cross coupling of amines with iodobenzene. Among them, the catalytic ability of Cu@C composites increased as their surface carbon's carburization degree improved.
Well-defined copper(I) amido complex and aryl iodides reacting to form aryl amines
Delp, Samuel A.,Goj, Laurel A.,Pouy, Mark J.,Munro-Leighton, Colleen,Lee, John P.,Gunnoe, T. Brent,Cundari, Thomas R.,Petersen, Jeffrey L.
, p. 55 - 57 (2011)
The CuI complex (IPr)Cu(NHPh) {IPr = 1,3-bis(2,6- diisopropylphenyl)imidazol-2-ylidene} reacts with aryl iodides to form diaryl amine products and (IPr)Cu(I), which was confirmed by independent synthesis and characterization. For the reaction with iodobenzene, the products are diphenylamine and aniline. Protection of the hydrogen para to the iodo functionality with ortho-methyl groups results in quantitative conversion to diaryl amine. Combined computational and experimental studies suggest that C-N bond formation most likely occurs via an oxidative addition/reductive elimination sequence.
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Grillot
, p. 2124 (1944)
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PHOTOCHEMISTRY OF 1,3-DIPHENYLTRIAZENE IN VARIOUS MEDIA. I: PHOTOLYSIS IN LIQUID SOLUTIONS.
Baro,Dudek,Luther,Troe
, p. 1155 - 1161 (1983)
1,3-Diphenyltriazene has been irradiated at 360 nm in various liquid solutions. Reversible trans-cis photoisomerization has been detected in solvents which do not form hydrogen bonds. Irreversible photolysis is observed with an appreciable amount of cage recombination products in all solvents. This reaction is well suited for a study in solid environments.
Room-temperature palladium-catalyzed amination of aryl bromides and chlorides and extended scope of aromatic C-N bond formation with a commercial ligand
Hartwig, John F.,Kawatsura, Motoi,Hauck, Sheila I.,Shaughnessy, Kevin H.,Alcazar-Roman, Luis M.
, p. 5575 - 5580 (1999)
The reactions of aryl bromides with amines occurs at room temperature when using Pd(0) and P(t-Bu)3 in a 1:1 ratio, and the reactions of aryl chlorides occur at room temperature or 70 °C. The arylation of indoles and the new arylation of carbamates also occur when using P(t-Bu)3 as ligand.
Low-valent titanium mediated deprotection of N-allyl/benzyl amines: A new approach
Talukdar,Banerji
, p. 813 - 818 (1995)
A novel low-valent titanium (LVT) mediated cleavage of N-allyl/benzyl amines is reported. Regio- and chemo-selective cleavages were also observed.
Copper-Catalyzed Allylation of Amines with Cyclopropyldiphenylsulfonium Trifluoromethanesulfonate
Ma, Yu,Tian, Ze-Yu,Zhang, Cheng-Pan,Zheng, Shuang-Yang
supporting information, (2022/03/15)
Cyclopropyldiphenylsulfonium salt, a famous ylide precursor previously extensively employed in the preparation of cyclic compounds, has been successfully utilized as an efficient allylation reagent in this work. The copper-catalyzed reactions of cyclopropyldiphenylsulfonium trifluoromethanesulfonate with amines in the presence of an appropriate ligand provided the N-allylated products in good yields. Aliphatic/ aromatic amines and primary/secondary amines were all converted under mild reaction conditions. This protocol was also applicable to N-functionalization of drug molecules, supplying the corresponding N-allylated compounds in satisfactory yields. The reaction, which showed good functional group tolerance with a wide range of substrates and excellent chemoselectivity, offers an interesting method for the synthesis of N-allyl amines.
A facile and versatile electro-reductive system for hydrodefunctionalization under ambient conditions
Huang, Binbin,Guo, Lin,Xia, Wujiong
supporting information, p. 2095 - 2103 (2021/03/26)
A general electrochemical system for reductive hydrodefunctionalization is described, employing the inexpensive and easily available triethylamine (Et3N) as a sacrificial reductant. This protocol is characterized by facile operation, sustainable conditions, and exceptionally wide substrate scope covering the cleavage of C-halogen, N-S, N-C, O-S, O-C, C-C and C-N bonds. Notably, the selectivity and capability of reduction can be conveniently switched by simple incorporation or removal of an alcohol as a co-solvent.
N-Heterocyclic Carbene Palladium(II) Amine Complexes: The Role of Primary Aryl- or Alkylamine Binding and Applications in the Buchwald-Hartwig Amination Reaction
Chen, Ming-Tsz,Hsu, Yu-Cheng
supporting information, (2021/12/24)
N-heterocyclic carbene-palladium(II) amine complexes bearing primary aryl- or alkylamines were synthesized. The prepared complexes were characterized by single crystal X-ray diffraction as well as NMR spectroscopy. These complexes exhibited good catalytic activities for the Buchwald-Hartwig amination reaction of aryl chlorides to afford arylated anilines under mild conditions. All reactions were carried out in air and all starting materials were used as supplied without purification. 21 expected coupling products were obtained in moderate to high yields under optimum conditions.
