3680-04-4Relevant academic research and scientific papers
Copper(I)-Catalyzed Asymmetric 1,4-Conjugate Hydrophosphination of α,β-Unsaturated Amides
Li, Yan-Bo,Tian, Hu,Yin, Liang
supporting information, p. 20098 - 20106 (2021/01/01)
A catalytic asymmetric conjugate hydrophosphination of α,β-unsaturated amides is accomplished by virtue of the strong nucleophilicity of copper(I)-PPh2 species, which provides an array of chiral phosphines bearing an amide moiety in high to excellent yields with excellent enantioselectivity. Furthermore, the dynamic kinetic resolution of unsymmetrical diarylphosphines (HPAr1Ar2) is successfully carried out through the copper(I)-catalyzed conjugate addition to α,β-unsaturated amides, which affords P-chiral phosphines with good-to-high diastereoselectivity and high enantioselectivity. 1H NMR studies show that the precoordination of HPPh2 to copper(I)-bisphosphine complex is critical for the efficient deprotonation by Barton's Base. Moreover, the relative stability of the copper(I)-(R,RP)-TANIAPHOS complex in the presence of excessive HPPh2, confirmed by 31P NMR studies, is pivotal for the high asymmetric induction, as the ligand exchange between bisphosphine and HPPh2 would significantly reduce the enantioselectivity. At last, a double catalytic asymmetric conjugate hydrophosphination furnishes the corresponding product in high yield with high diastereoselectivity and excellent enantioselectivity, which is transformed to a chiral pincer palladium complex in moderate yield. This chiral palladium complex is demonstrated as an excellent catalyst in the asymmetric conjugate hydrophosphination of chalcone.
Preparation method of cinnamamide (by machine translation)
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Paragraph 0183-0189, (2020/05/01)
The synthesis system disclosed by the invention has the advantages of simple :(1) reaction conditions, wide, reaction conditions, reaction conditions, wide ;(2) substrate range, high yield (1) and wide application range, and the reaction liquid, can be used as an anti-cancer drug, anti-anti-tumor and spice precursor compound in an organic solvent to prepare a corresponding cinnamide compound, product cinnamide . The synthesis system disclosed by the invention has a broad spectrum . The synthesis system disclosed by the invention has a broad spectrum of biological activity, and is suitable for popularization and application, in the following steps, synthesizing cinnamic acid and thiuram disulfide as a raw material, in an organic, solvent, and purifying, parts by mass, separation and purification of the obtained reaction, solution in an organic solvent. (by machine translation)
Radical α,β-Dehydrogenation of Saturated Amides via α-Oxidation with TEMPO under Transition Metal-Free Conditions
Wang, Mei-Mei,Sui, Guo-Hui,Cui, Xian-Chao,Wang, Hui,Qu, Jian-Ping,Kang, Yan-Biao
, p. 8267 - 8274 (2019/06/27)
A transition metal-free radical process for the selective α,β-dehydrogenation of saturated amides under mild conditions is developed. Utilizing radical activation strategy, the challenging issue associated with the low α-acidity of amides is resolved. For the first time, α,β-unsaturated Weinreb amides and acrylamides could be efficiently prepared directly from corresponding saturated amides. Mechanistic studies confirm the radical nature of this transformation. Two gram scale α,β-dehydrogenation have also been performed to demonstrate the utility of this method.
Chemoselective α,β-Dehydrogenation of Saturated Amides
Teskey, Christopher J.,Adler, Pauline,Gon?alves, Carlos R.,Maulide, Nuno
, p. 447 - 451 (2019/01/04)
We report a method for the selective α,β-dehydrogenation of amides in the presence of other carbonyl moieties under mild conditions. Our strategy relies on electrophilic activation coupled to in situ selective selenium-mediated dehydrogenation. The α,β-unsaturated products were obtained in moderate to excellent yields, and their synthetic versatility was demonstrated by a range of transformations. Mechanistic experiments suggest formation of an electrophilic SeIV species.
Vanadium(V)-Induced Oxidative Cross-Coupling of Various Boron and Silyl Enolates
Amaya, Toru,Osafune, Yuma,Maegawa, Yusuke,Hirao, Toshikazu
, p. 1301 - 1304 (2017/06/23)
Intermolecular oxidative cross-coupling of two different enolates is one of the most useful reactions to synthesize unsymmetrical 1,4-dicarbonyl compounds. In this study, the oxovanadium(V)-induced intermolecular oxidative cross-coupling of enolates afforded unsymmetrical 1,4-dicarbonyl compounds. Various boron and silyl enolates underwent the formation of ketone–ester, ester–ketone, ester–ester, amide–ketone and amide–ester coupling products. These results clearly show the versatility of the present oxidative cross-coupling protocol.
Sunlight assisted direct amide formation: Via a charge-transfer complex
Cohen, Irit,Mishra, Abhaya K.,Parvari, Galit,Edrei, Rachel,Dantus, Mauricio,Eichen, Yoav,Szpilman, Alex M.
supporting information, p. 10128 - 10131 (2017/09/23)
We report on the use of charge-transfer complexes between amines and carbon tetrachloride, as a novel way to activate the amine for photochemical reactions. This principle is demonstrated in a mild, transition metal free, visible light assisted, dealkylative amide formation from feedstock carboxylic acids and amines. The low absorption coefficient of the complex allows deep light penetration and thus scale up to a gram scale.
One-pot synthesis of amides from carboxylic acids activated using thionyl chloride
Leggio,Belsito,De Luca,Di Gioia,Leotta,Romio,Siciliano,Liguori
, p. 34468 - 34475 (2016/06/13)
A one-pot synthesis of secondary and tertiary amides from carboxylic acids and amines by using SOCl2 has been developed. Also when sterically hindered amines were used as the starting materials, excellent yields of the corresponding amides were obtained. The amidation of N-protected α-amino acids with secondary amines proceeds effectively with good yields. The process works well also in the presence of acid sensitive groups and occurs with almost complete retention of stereochemical integrity of chiral substrates. This protocol could be extended to industrial large-scale production processes.
Borane-Catalyzed Reductive α-Silylation of Conjugated Esters and Amides Leaving Carbonyl Groups Intact
Kim, Youngchan,Chang, Sukbok
supporting information, p. 218 - 222 (2016/01/25)
Described herein is the development of the B(C6F5)3-catalyzed hydrosilylation of α,β-unsaturated esters and amides to afford synthetically valuable α-silyl carbonyl products. The α-silylation occurs chemoselectively, thus leaving the labile carbonyl groups intact. The reaction features a broad scope of both acyclic and cyclic substrates, and the synthetic utility of the obtained α-silyl carbonyl products is also demonstrated. Mechanistic studies revealed two operative steps: fast 1,4-hydrosilylation of conjugated carbonyls and then slow silyl group migration of a silyl ether intermediate.
Synthesis of Cinnamanilide Derivatives and Their Antioxidant and Antimicrobial Activity
Nimse, Satish Balasaheb,Pal, Dilipkumar,Mazumder, Avijit,Mazumder, Rupa
, (2016/01/15)
The amide derivatives of cinnamic acid were synthesized and their antimicrobial and antioxidant activities were investigated. The investigation of antimicrobial potentials of the compounds demonstrated a strong activity against 21 bacterial strains comprising Gram-positive and Gram-negative bacteria. Compounds 2a, 2b, and 3b showed strong antimicrobial activity against all microorganisms with the pMIC value ranging from 2.45 to 3.68. Compounds 2a, 3a, and 3b demonstrated strong antioxidant activity with % inhibition of the DPPH radical of 51% (±1.14), 41% (±1.01), and 50% (±1.23), respectively. These findings indicate that the amide derivatives of the cinnamic acid possess strong antibacterial and antioxidant activities.
Tandem superelectrophilic hydroarylation of CC bond and carbonyl reduction in cinnamides: Synthetic rout to 3,3-diarylpropylamines, valuable pharmaceuticals
Zakusilo, Dmitry N.,Ryabukhin, Dmitry S.,Boyarskaya, Irina A.,Yuzikhin, Oleg S.,Vasilyev, Aleksander V.
, p. 102 - 108 (2015/02/02)
Cinnamides ArCHCHCONRR′ in reactions with arenes Ar′H under the action of Bronsted (TfOH, FSO3H) or Lewis (AlBr3) superacids at rt for 1-2 h give CC bond hydroarylation products ArAr′CHCH2CONRR′ in yields of 63-98%. Reduction (LiAlH4/Et2O) of carbonyl group in the latter results in the formation of 3,3-diarylpropylamines ArAr′CHCH2CH2NRR′, valuable drugs. The reaction intermediates, superelectrophilic dications ArC+H-CH2C(OH+)NRR′, have been characterized by DFT calculations in terms of global electrophilicity index, natural charges, and atomic orbitals contributions.
