7472-54-0Relevant academic research and scientific papers
Nickel-Catalyzed Cross-Electrophile Coupling between C(sp2)-F and C(sp2)-Cl Bonds by the Reaction of ortho-Fluoro-Aromatic Amides with Aryl Chlorides
Nohira, Itsuki,Chatani, Naoto
, p. 4644 - 4649 (2021)
Ni-catalyzed cross-electrophile coupling between C(sp2)-F bonds in ortho-fluoro-substituted aromatic amides and C(sp2)-Cl bonds in aryl chlorides in the presence of Zn as a reductant and LiOtBu as a base, and LiCl and ZnCl2 as additives is reported. The reaction displayed excellent functional group tolerance and a broad substrate scope. The reaction was also applicable to cross-electrophile coupling between C(sp2)-F and C(sp2)-O bonds in an aryl tosylate and a triflate derivative.
Nickel-Catalyzed Reductive Cross-Coupling of N-Acyl and N-Sulfonyl Benzotriazoles with Diverse Nitro Compounds: Rapid Access to Amides and Sulfonamides
Qu, Erdong,Li, Shangzhang,Bai, Jin,Zheng, Yan,Li, Wanfang
supporting information, p. 58 - 63 (2021/12/27)
Herein we report a Ni-catalyzed reductive transamidation of conveniently available N-acyl benzotriazoles with alkyl, alkenyl, and aryl nitro compounds, which afforded various amides with good yields and a broad substrate scope. The same catalytic reaction conditions were also applicable for N-sulfonyl benzotriazoles, which could undergo smooth reductive coupling with nitroarenes and nitroalkanes to afford the corresponding sulfonamides.
In Situ Formation of Cationic π-Allylpalladium Precatalysts in Alcoholic Solvents: Application to C-N Bond Formation
Steinsoultz, Philippe,Bailly, Aurélien,Wagner, Patrick,Oliva, Estefania,Schmitt, Martine,Grimaud, Laurence,Bihel, Frédéric
, p. 560 - 567 (2022/01/03)
We report an efficient Buchwald-Hartwig cross-coupling reaction in alcoholic solvent, in which a low catalyst loading showed excellent performance for coupling aryl halides (I, Br, and Cl) with a broad set of amines, amides, ureas, and carbamates under mild conditions. Mechanistically speaking, in a protic and polar medium, extremely bulky biarylphosphine ligands interact with the dimeric precatalyst [Pd(π-(R)-allyl)Cl]2 to form the corresponding cationic complexes [Pd(π-(R)-allyl)(L)]Cl in situ and spontaneously. The resulting precatalyst further evolves under basic conditions into the corresponding L-Pd(0) catalyst, which is commonly employed for cross-coupling reactions. This mechanistic study highlights the prominent role of alcoholic solvents for the formation of the active catalyst.
Generation of Oxyphosphonium Ions by Photoredox/Cobaloxime Catalysis for Scalable Amide and Peptide Synthesis in Batch and Continuous-Flow
Chen, Xiangyang,Houk, Kendall N.,Mo, Jia-Nan,Su, Junqi,Umanzor, Alexander,Zhang, Zheng,Zhao, Jiannan
supporting information, (2022/01/06)
Phosphine-mediated deoxygenative nucleophilic substitutions, such as the Mitsunobu reaction, are of great importance in organic synthesis. However, the conventional protocols require stoichiometric oxidants to trigger the formation of the oxyphosphonium i
IPr# - highly hindered, broadly applicable N-heterocyclic carbenes
Flach, Carol,Lalancette, Roger,Li, Guangchen,Mendelsohn, Richard,Meng, Guangrong,Szostak, Michal,Szostak, Roman,Zhao, Qun
, p. 10583 - 10589 (2021/08/20)
IPr (IPr = 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene) represents the most important NHC (NHC = N-heterocyclic carbene) ligand throughout the field of homogeneous catalysis. Herein, we report the synthesis, catalytic activity, and full structural and electronic characterization of novel, sterically-bulky, easily-accessible NHC ligands based on the hash peralkylation concept, including IPr#, Np# and BIAN-IPr#. The new ligands have been commercialized in collaboration with Millipore Sigma: IPr#HCl, 915653; Np#HCl; 915912; BIAN-IPr#HCl, 916420, enabling broad access of the academic and industrial researchers to new ligands for reaction optimization and screening. In particular, the synthesis of IPr# hinges upon cost-effective, modular alkylation of aniline, an industrial chemical that is available in bulk. The generality of this approach in ligand design is demonstrated through facile synthesis of BIAN-IPr# and Np#, two ligands that differ in steric properties and N-wingtip arrangement. The broad activity in various cross-coupling reactions in an array of N-C, O-C, C-Cl, C-Br, C-S and C-H bond cross-couplings is demonstrated. The evaluation of steric, electron-donating and π-accepting properties as well as coordination chemistry to Au(i), Rh(i) and Pd(ii) is presented. Given the tremendous importance of NHC ligands in homogenous catalysis, we expect that this new class of NHCs will find rapid and widespread application.
LIGANDS FOR TRANSITION METAL CATALYSTS
-
Page/Page column 35-36, (2021/07/17)
Provided herein are a new class of extremely sterically-bulky, easily prepared N-heterocyclic carbene (NHC) ligands of Formula I, or a salt, solvate, geometric isomer, or stereoisomer thereof. The ligands are readily synthetically accessible exploiting the cost-effective, modular alkylation of anilines, an industrial chemical that is available in bulk. The NHC ligands form effective catalysts with transition metals such as Pd.
PCl3-mediated transesterification and aminolysis of tert-butyl esters via acid chloride formation
Wu, Xiaofang,Zhou, Lei,Li, Fangshao,Xiao, Jing
, p. 491 - 497 (2021/01/20)
A PCl3-mediated conversion of tert-butyl esters into esters and amides in one-pot under air is developed. This novel protocol is highlighted by the synthesis of skeletons of bioactive molecules and gram-scale reactions. Mechanistic studies revealed that this transformation involves the formation of an acid chloride in situ, which is followed by reactions with alcohols or amines to afford the desired products.
Carboxylic Acid Deoxyfluorination and One-Pot Amide Bond Formation Using Pentafluoropyridine (PFP)
Brittain, William D. G.,Cobb, Steven L.
supporting information, p. 5793 - 5798 (2021/08/01)
This work describes the application of pentafluoropyridine (PFP), a cheap commercially available reagent, in the deoxyfluorination of carboxylic acids to acyl fluorides. The acyl fluorides can be formed from a range of acids under mild conditions. We also demonstrate that PFP can be utilized in a one-pot amide bond formation via in situ generation of acyl fluorides. This one-pot deoxyfluorination amide bond-forming reaction gives ready access to amides in yields of ≤94%.
COMPLEXES OF N-HETEROCYCLIC CARBENES FOR TRANSITION METAL CATALYSIS
-
Paragraph 34, (2021/07/17)
Described herein is a new class of highly active Pd(II)-NHC complexes bearing anilines as throw-away ligands. These catalysts are well-defined, air- and moisture-stable and can be easily purified by chromatographic techniques. High activity and generality has been exemplified in the Suzuki-Miyaura cross-coupling by C-N, C-O and C-Cl cleavage. Facile syntheses of these catalysts is also described.
Room-temperature copper-catalyzed electrophilic amination of arylcadmium iodides with ketoximes
Korkmaz, Adem
, p. 3119 - 3125 (2021/05/10)
We started our study by preparation two ketoximes. Later, there were studies to reveal these ketoximes' effects in the electrophilic amination reaction with organocadmium reagents. Primarily, it was observed that arylcadmium iodides could not be reacted with ketoximes at room temperature in the absence of a catalyst. CuCN was a suitable catalyst for this electrophilic amination reaction of arylcadmium iodides and allowed the preparation of functionalized aniline derivatives in good yields under mild reaction conditions. We obtained the results indicated that the yield of primary arylamines was strongly dependent on the steric and electronic effects of organocadmium reagent and amination agent. In the case of both amination reagents, meta-substituted arylamines were obtained in higher yields than para-substituted arylamines. We observed that acetone O-(4-chlorophenylsulfonyl)oxime, 1, as an aminating agent, was more successful than acetone O-(2-Naphthylsulfonyl)oxime, 2, in the synthesis of functionalized arylamines by electrophilic amination of corresponding aryl cadmium iodides. In this method, there is no cadmium release to the environment.
