22031-64-7Relevant academic research and scientific papers
Regio- and diastereoselective synthesis of trans-dihydrofuran-3carboxamides by radical addition of 1,3-dicarbonyl compounds to acrylamides using manganese(III) acetate and determination of exact configuration by X-ray crystallography
Yilmaz, Mehmet,Ustalar, Ash,U?an, Bedriye,Pekel, A. Tar?k
, p. 79 - 91 (2016)
In this study, we investigated the radical addition of 1,3-dicarbonyl compounds to acrylamide derivatives including phenyl, 2-thienyl and 5-methyl-2-furyl groups mediated by manganese(III) acetate. trans-3-Carboxamide-dihydrofurans were obtained in modarate to good yields, as well as regio- and diastereoselectievly. Structural analyses of these compounds were made by NMR techniques such as HMBC and NOSY spectra. Also, exact configuration and structures of these (7b, 7i and 7j) compounds were determined by X-ray crystallography.
Ammonium salts from polymer-bound N-hydroxysuccinimide as solid-supported reagents for EDC-mediated amidations
Chinchilla, Rafael,Dodsworth, David J.,Nájera, Carmen,Soriano, José M.
, p. 463 - 466 (2003)
New ammonium and alkylammonium salts derived from a polymeric N-hydroxysuccinimide (P-HOSu) have been prepared and used for the amidation of carboxylic acids and amino acids mediated by 1-ethyl-3-(3′-dimethylamino-propyl)carbodiimide hydrochloride (EDC). These polymer-supported ammonium salts afforded the corresponding amides in good yield, without detectable α-racemization and with easy recovery of the P-HOSu after the amidation reaction, being especially suitable for the amidation of Fmoc-protected amino acids.
The HWE reaction in solid - liquid two phase system for the synthesis of α,β-unsaturated amides
Petrova, Jordanka,Momchilova, Snezhana,Vassilev, Nikolay G.
, p. 87 - 94 (2000)
The Horner-Wadsworth-Emmons (HWE) reaction of the diethyl ester of 2-amino-2-oxoethylphosphonic acid 1 as well as of diethyl ester of the 2-dimethylamino-2-oxoethylphosphonic acid 2 with some aldehydes and ketones 3 in liquid-solid two phase system is used for the preparation of α,β-unsaturated amides 4, 5. The synthesis is carried out in mild conditions (room temperature, KOH, K2CO3, CaO) in the absence of a catalyst or in the absence of a solvent, and leads in very high (E)-stereoselectivity and in high yields to en-amides.
Facile and highly selective conversion of nitriles to amides via indirect acid-catalyzed hydration using TFA or AcOH-H2SO4
Moorthy, Jarugu Narasimha,Singhal, Nidhi
, p. 1926 - 1929 (2005)
(Chemical Equation Presented) Both aliphatic and aromatic nitriles are conveniently and selectively converted in a single step, via an indirect acid-catalyzed hydration, into the corresponding amides in 1-8 h using a TFA-H2SO4 mixture as a reagent system. Although the same reagent did not work for the sterically hindered nitriles such as mesitonitrile, the transformation could be accomplished by changing TFA to AcOH at higher temperatures (>90°C).
Iron-catalyzed hydroaminocarbonylation of alkynes: Selective and efficient synthesis of primary α,β-unsaturated amides
Huang, Zijun,Jiang, Xiongwei,Lan, Donghui,Li, Yuehui,Pi, Shaofeng,Tan, Zhengde,Tang, Jia,Xie, Tianle,Yi, Bing,Zhang, Minmin
supporting information, (2022/02/22)
α,β-Unsaturated primary amides are important intermediates and building blocks in organic synthesis. Herein, we report a ligand-free iron-catalyzed hydroaminocarbonylation of alkynes using NH4HCO3 as the ammonia source, enabling the highly efficient and regioselective synthesis of linear α,β-unsaturated primary amides. Various aromatic and aliphatic alkynes are transformed into the desired linear α,β-unsaturated primary amides in good to excellent yields. Further studies show that using NH4HCO3 as the ammonia source is key to obtain good yields and selectivity. The utility of this route is demonstrated with the synthesis of linear α,β-unsaturated amides including vanilloid receptor-1 antagonist TRPV-1.
Nitrogen Atom Transfer Catalysis by Metallonitrene C?H Insertion: Photocatalytic Amidation of Aldehydes
Schmidt-R?ntsch, Till,Verplancke, Hendrik,Lienert, Jonas N.,Demeshko, Serhiy,Otte, Matthias,Van Trieste, Gerard P.,Reid, Kaleb A.,Reibenspies, Joseph H.,Powers, David C.,Holthausen, Max C.,Schneider, Sven
, (2022/01/20)
C?H amination and amidation by catalytic nitrene transfer are well-established and typically proceed via electrophilic attack of nitrenoid intermediates. In contrast, the insertion of (formal) terminal nitride ligands into C?H bonds is much less developed and catalytic nitrogen atom transfer remains unknown. We here report the synthesis of a formal terminal nitride complex of palladium. Photocrystallographic, magnetic, and computational characterization support the assignment as an authentic metallonitrene (Pd?N) with a diradical nitrogen ligand that is singly bonded to PdII. Despite the subvalent nitrene character, selective C?H insertion with aldehydes follows nucleophilic selectivity. Transamidation of the benzamide product is enabled by reaction with N3SiMe3. Based on these results, a photocatalytic protocol for aldehyde C?H trimethylsilylamidation was developed that exhibits inverted, nucleophilic selectivity as compared to typical nitrene transfer catalysis. This first example of catalytic C?H nitrogen atom transfer offers facile access to primary amides after deprotection.
Organocatalytic Trans Semireduction of Primary and Secondary Propiolamides: Substrate Scope and Mechanistic Studies
Grams, R. Justin,Lawal, Monsurat M.,Szwetkowski, Connor,Foster, Daniel,Rosenblum, Carol Ann,Slebodnick, Carla,Welborn, Valerie Vaissier,Santos, Webster L.
supporting information, p. 172 - 178 (2021/10/14)
We report a chemoselective, phosphine-catalyzed semireduction of primary and secondary propiolamides. In the presence of stoichiometric pinacolborane and catalytic n-tributylphosphine, a variety of propiolamides were successfully converted to the corresponding acrylamides in excellent yield with (E)-stereoselectivity. The reaction condition is tolerant of various functional groups including alkene, alkyne, ketone, or ester. Deuterium labeling studies established that the hydride from activated pinacolborane is added to the α-carbon and the proton on the amide nitrogen is abstracted by the ?-carbon to furnish the (E)-acrylamides. DFT calculations revealed a clear energetic driving force for the (E)- over the (Z)-isomer. (Figure presented.).
Manganese Catalyzed Enantioselective Epoxidation of α,β-Unsaturated Amides with H2O2
Ottenbacher, Roman V.,Kurganskiy, Vladimir I.,Talsi, Evgenii P.,Bryliakov, Konstantin P.
supporting information, p. 2778 - 2782 (2021/04/29)
Herewith, we report the enantioselective epoxidation of electron-deficient cis- and trans-α,β-unsaturated amides with the environmentally benign oxidant H2O2. The catalysts - manganese complexes with bis-amino-bis-pyridine and structurally related ligands - exhibit reasonably high efficiency (up to 100 TON) and excellent chemo- and enantioselectivity (up to 100% and 99% ee, respectively). Crucially, the cis-enamides epoxidation enantioselectivity and yield are dramatically enhanced by the presence of NH-moiety, which effect can be explained by the hydrogen bonding interaction between the cis-enamide substrate and the manganese based oxygen transferring species. (Figure presented.).
Pd(II)-Catalyzed CC Bond Cleavage by a Formal Group-Exchange Reaction
Ye, Runyou,Zhu, Maoshuai,Yan, Xufei,Long, Yang,Xia, Ying,Zhou, Xiangge
, p. 8678 - 8683 (2021/07/26)
A chelation-assisted palladium-catalyzed CC bond cleavage of α, β-unsaturated ketone to form alkenyl nitrile in the presence of nitrile is disclosed on the basis of a formal group-exchange reaction formulated as C1C2 + C3 → C1C3 + C2, differing from normal alkene oxidative cleavage and metathesis type. The isolated key active Pd(II) complex as well as deuterium-labeled experiment revealed the necessity of the chelation group, and a plausible catalytic pathway was proposed.
Systematic study on acylation of methyl 3-aminocrotonate with acid chlorides of aliphatic, aromatic and α, β-unsaturated acids: A comparative evaluation of the preference for regio- And stereoselectivity vis-à-vis 3-aminocrotononitrile
Mahalanabis, Kumar K.,Mukherjee, Attreyee
, p. 291 - 302 (2021/09/28)
Acylation of methyl 3-aminocrotonate 1a in benzene with a variety of aliphatic and aromatic acid chlorides including α, β-unsaturated acid chloride in the presence of an added organic base, (either pyridine or triethylamine) is reported. The preferred N, C-site selectivity in these reactions has been compared with the terminal selectivity of the products obtained previously on acylation of methyl 3-aminocrotononitrile 1b. A strong preference either for N- or C- selectivity in N, C-acylation has been observed for both 1a and 1b based on the choice of acid chlorides and added organic base. Interestingly, irrespective of the enamine 1a or 1b, acylation with α, β-unsaturated acid chlorides in the presence of triethylamine afforded 3,4-dihydropyridin-(2H)-one via [3.3] sigmatropic rearrangement of the corresponding intermediary N(E)-enamide. Accrued results show methyl 3-aminocrotonate to be a better precursor for preparation of enamides (N-acylated products) whereas 3-aminocrotononitrile is found to be a preferred choice for preparation of enaminones (C-acylated products). An attempt is made to offer a preliminary theoretical interpretation for observed site selectivity.
