3820-26-6Relevant academic research and scientific papers
Microwave-enhanced aromatic dehalogenation studies: A rapid deuterium-labelling procedure
Jones, John R.,Lockley, William J.S.,Lu, Shui-Yu,Thompson, Stewart P.
, p. 331 - 332 (2001)
Rapid (a number of N-4-picolyl-4-halogenobenzamides using deuterated formate as solid deuterium donor and either homogeneous or heterogeneous catalysts; the percentage deuterium incorporation is a function of the kind of solvent used.
Metal-Free C-C Coupling of an Allenyl Sulfone with Picolyl Amides to Access Vinyl Sulfones via Pyridine-Initiated in Situ Generation of Sulfinate Anion
Omer, Humair M.,Liu, Peng,Brummond, Kay M.
, p. 7959 - 7975 (2020/07/15)
Vinyl sulfones are privileged motifs known for their biological activity and synthetic utility. Synthetic transformations to efficiently access high-value compounds with these motifs are desired and sought after. Herein, a new procedure is described to fo
Methyl Esters as Cross-Coupling Electrophiles: Direct Synthesis of Amide Bonds
Zheng, Yan-Long,Newman, Stephen G.
, p. 4426 - 4433 (2019/05/08)
Amide bond formation and transition metal-catalyzed cross-coupling are two of the most frequently used chemical reactions in organic synthesis. Recently, an overlap between these two reaction families was identified when Pd and Ni catalysts were demonstrated to cleave the strong C-O bond present in esters via oxidative addition. When simple methyl and ethyl esters are used, this transformation provides a powerful alternative to classical amide bond formations, which commonly feature stoichiometric activating agents. Thus far, few redox-active catalysts have been demonstrated to activate the C(acyl)-O bond of alkyl esters, which makes it difficult to perform informed screening when a challenging reaction needs optimization. We demonstrate that Ni catalysts bearing diverse NHC, phosphine, and nitrogen-containing ligands can all be used to activate methyl esters and enable their use in direct amide bond formation.
Palladium-Catalyzed Direct Synthesis of Phenanthridones from Benzamides through Tandem N–H/C–H Arylation
Banerji, Biswadip,Chatterjee, Satadru,Chandrasekhar,Nayan, Chinmay,Killi, Sunil Kumar
supporting information, p. 5214 - 5218 (2017/09/29)
We report a palladium-catalyzed method for the direct synthesis of phenanthridones from benzamides in a single step. Unlike previous reports, the current protocol does not need any directing groups or any harsh conditions. This methodology has a wide functional group tolerance therefore a series of phenanthridones were synthesized with a yield up to 87 %. The efficacy of this protocol was further explored by synthesizing some important naturally occurring amaryllidaceae alkaloids in a single step with very good yields.
Construction of 1,2,4-Triazole Derivatives via Cyclocondensation of Alkylidene Dihydropyridines and Aryldiazonium Salts
Joshi, Madhur S.,Pigge, F.Christopher
supporting information, p. 5916 - 5919 (2016/11/29)
Alkylidene dihydropyridines (anhydrobases) prepared via dearomatization of N-acylated 4-(aminomethyl)pyridines participate in [3 + 2] cyclocondensation reactions with aryldiazonium cations to afford substituted 1,2,4-triazolium salts or neutral 1,2,4-tria
Tert -Butyl Peroxybenzoate Mediated Selective and Mild N-Benzoylation of Ammonia/Amines under Catalyst- and Solvent-Free Conditions
Yadav, Dilip Kumar T.,Bhanage, Bhalchandra M.
supporting information, p. 1862 - 1866 (2015/08/06)
A new protocol for the synthesis of amides from tert-butyl peroxybenzoate (TBPB) and ammonia/amines has been developed under catalyst- and solvent-free conditions. The ammonia, primary and secondary amines reacted smoothly with TBPB to furnish the corresponding primary, secondary, and tertiary amides in excellent yields. TBPB proved to be an efficient and highly chemoselective benzoylating reagent for aliphatic amines in the presence of aromatic amines/hydroxyl groups.
Green synthesis of benzamides in solvent- and activation-free conditions
Alalla, Affef,Merabet-Khelassi, Mounia,Aribi-Zouioueche, Louisa,Riant, Olivier
supporting information, p. 2364 - 2376 (2014/07/22)
Herein, we describe a clean and ecocompatible pathway for both N-benzoylation and N-acetylation of anilines, amines, diamines, and aminoalcohols using three enol esters with good yields. We have improved the use of vinyl benzoate for the direct introduction of a benzamido-moiety under solvent- and activation-free conditions. The recovered amides are easily isolated by crystallization. Copyright
On DABAL-Me3 promoted formation of amides
Dubois, Nathalie,Glynn, Daniel,McInally, Thomas,Rhodes, Barrie,Woodward, Simon,Irvine, Derek J.,Dodds, Chris
, p. 9890 - 9897 (2013/10/22)
The range and utility of DABAL-Me3 couplings of methyl esters and free carboxylic acids with primary and secondary amines under a variety of conditions (reflux, sealed tube, microwave) has been compared for a significant range of coupling partners of relevance to the preparation of amides of interest in pharmaceutical chemistry. Commercial microwave reactors promote the fastest couplings and allow the use of significantly sterically hindered amines (primary and secondary) and carboxylic acids derivatives. The influence of microwave energy on the reaction system was shown to be typically related to thermal effects (over-pressuring and superheating).
Free energy and solvent dependence of intramolecular electron transfer in donor-substituted Re(I) complexes
Brent MacQueen,Schanze, Kirk S.
, p. 7470 - 7479 (2007/10/02)
A comprehensive investigation of photoinduced Intramolecular electron transfer (ET) in a of six complexes of the type fac-(b)Re1(CO)3-D (where b is a diimine ligand and D is a dimethylaniline donor) is reported. Photoexcitation of the dπ (Re) → π* (diimine) metal-to-ligand charge-transfer excited state initiates a sequence of forward and beck ET reactions: (b) ReI(CO)3-D → hv (b-) ReII(CO)3-D → ΔGFETkFET (b-) ReI(CO)3-D+ →kBETΔBET (b)ReI(CO)3-D The driving force for forward and ET (ΔGFET and ΔGBET, respectively) is varied by the electron demand of the diimine ligand. Cyclic voltammetry and steady-state emission studies were carried out for each complex in three solvents (CH2CL2, DMF, and CH3CN) to allow estimation of Δgfet and Δgbet. The forward ET reactions are weakly exothermic (-0.5 eV FET BET FET) for each of the complexes in the three solvents were determined by using time-resolved emission spectroscopy. The forward ET rate ranges from 107 s-1 to > 109 s-1 and is strongly dependent on ΔGFET and solvent polarity. The dependence of kFET on ΔGFET is consistent with nonadiabatic semiclassical Marcus theory. The solvent of kFET that suggests that the reorganization energy increases with solvent polarity in a manner that Is consistent with the Marcus-Hush dielectric continuum model. Rates for back ET (kBET) were determined by using laser flash photolysis in two solvents. The back ET rat ranges from 107 s-1 to 5 × 108 s-1 and is not solvent dependent. Interestingly, kBET displays a weak, inverted dependence on ΔGBET. Analysis of the rate using a multimode quantum mechanical expression suggests that a possible explation for the weak free-energy dependence may be that metal complex-based high-frequency acceptor modes are coupled to the back ET process.
Identification of a Chromogen in the Assay of Hippuric Acid with Acetic Anhydride, Pyridine, and 4-(Dimethylamino)benzaldehyde
Hirota, Kazuhiro,Ikeda, Mikiko,Kawase, Michi,Ohmori, Shinji
, p. 2087 - 2090 (2007/10/02)
A yellow chromogen, formed in the assay system for hippuric acid which consists of acetic anhydride, pyridine, and 4-(dimethylamino)benzaldehyde, was isolated, and the structure was determined to be 4-(1-acetyl-4(1H)-pyridylidene)-2-phenyl-2-oxazolin-5-one.The structure was confirmed by the chemical conversion to known compounds as well as by NMR spectra.The conversion was accomplished by hydrolysis of the chromogen to 4-((benzoylamino)methyl)pyridine, 4-(aminomethyl)pyridine, and benzoic acid via 5-hydroxy-2-phenyl-4-(4-pyridyl)oxazole. 4-(Dimethylamino)benzaldehyde included in the assay system increased the production of the chromogen.The formation mechanism of the chromogen via an intermediate susceptible to oxidation was proposed.
