55572-47-9Relevant academic research and scientific papers
Highly efficient and facile synthesis of β-enaminones catalyzed by diphenylammonium triflate
Zhao, Ting-Ting,Song, Jiang-Long,Hong, Feng-Qing,Xia, Jian-Sheng,Li, Jian-Jun
, p. 2857 - 2868 (2019/08/21)
Abstract: The catalytic performance of diphenylammonium triflates as an organocatalyst in the synthesis of β-enaminones from various substituted β-diketones and amides (or amines) were evaluated. A wide range of β-enaminones were efficiently synthesized in good to excellent yields under mild reaction conditions. Applying diphenylammonium triflate (DPAT) as catalyst makes this protocol cost-effective, low corrosive and easy to handle. Graphic abstract: [Figure not available: see fulltext.].
Hypervalent iodane mediated reactions of: N -acetyl enamines for the synthesis of oxazoles and imidazoles
Xu, Kang,Yang, Ruiqi,Yang, Shuang,Jiang, Cheng,Ding, Zhenhua
supporting information, p. 8977 - 8981 (2019/10/28)
A hypervalent iodane reagent used for the intramolecular cyclization of N-acetyl enamines and intermolecular cyclocondensation of enamines and nitriles was investigated. The reaction was performed under mild conditions and gave oxazoles and imidazoles, respectively, in moderate to excellent yields. This transformation exhibits good reactivity, selectivity and functional group tolerance. The selectivity of the intra- or intermolecular reaction is dependent on the structure of N-acetyl enamines.
Nickel-catalyzed enantioselective hydrogenation of β-(acylamino)acrylates: Synthesis of chiral β-amino acid derivatives
Li, Xiuxiu,You, Cai,Li, Shuailong,Lv, Hui,Zhang, Xumu
, p. 5130 - 5133 (2017/11/06)
The nickel-catalyzed asymmetric hydrogenation of β-(acylamino)acrylates has been developed, affording chiral β-amino acid derivatives with excellent yields (95-99% yield) and enantioselectivities (97-99% ee). With the Ni-Binapine system, high enantioselectivities (98-99% ee) have also been obtained in the hydrogenation of Z/E isomeric mixtures of β-alkyl and β-aryl β-(acylamino)acrylates. The synthesis of chiral β-amino acid derivatives on a gram scale has also been achieved with 0.2 mol % catalyst loading.
A optically active 3 - amino butanol and 3 - aminobutyric acid preparation method (by machine translation)
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Paragraph 0107; 0108, (2017/07/01)
The invention discloses a method of optically active 3 - amino butanol and 3 - aminobutyric acid preparation method. Wherein optically active 3 - amino butyl alcohol preparation method comprises the following steps: in a solvent, in the borohydride reducing agent and a Lewis acid under the action of the, shown as 65 shown in the reduction reaction of compound, production like type 14 indicated by the compound. Optically active 3 - aminobutyric acid preparation method comprises the following steps: shown as 64 a compound represented by the hydrolytic reaction, production like type 65 compound of formula. Preparation method of this invention the raw material is cheap, simple operation, the process route is short, the raw material is not hazardous, high yield, produce little material waste, is beneficial for the protection of the environment, high conversion rate of raw materials, product chemical purity and high optical purity, and is easy to realize industrial. (by machine translation)
Eco-friendly, catalyst and solvent-free, synthesis of acetanilides and N-benzothiazole-2-yl-acetamides
Cunha, Silvio,De Santana, Louren?o L. B.
, p. 1137 - 1144 (2017/05/01)
An expeditious and green synthesis of acetamides in a solvent-free simple way is described, without catalyst or additives, and in good yield by an instantaneous reaction of anilines or 2-aminothiazoles and acetic anhydride without external heating, and with simple purification. Sixteen substituted acetanilides and four N-benzothiazole-2-yl-acetamides were formed, but aliphatic amines of low molecular weight were not as effective as aromatic ones, and only cyclohexylamine and the enaminone ethyl 3-amino-2-butenoate afforded the corresponding acetamides in good yield.
Synthesis of β-amino acid derivatives via copper-catalyzed asymmetric 1,4-reduction of β-(acylamino)acrylates
Wu, Yan,Qi, Shan-Bin,Wu, Fei-Fei,Zhang, Xi-Chang,Li, Min,Wu, Jing,Chan, Albert S. C.
supporting information; experimental part, p. 1754 - 1757 (2011/05/12)
A new set of reaction conditions has been established to facilitate the copper-catalyzed enantioselective 1,4-reduction of β-(acylamino)acrylates toward a selection of β-alkyl-β-amino acid derivatives in high yields and with uniformly high ee values (up to 99%) irrespective of the use of (E)- or (Z)-substrates.
Pyrrole synthesis via allylic sp3 C-H activation of enamines followed by intermolecular coupling with unactivated alkynes
Rakshit, Souvik,Patureau, Frederic W.,Glorius, Frank
supporting information; experimental part, p. 9585 - 9587 (2010/09/10)
A conceptually novel pyrrole synthesis is reported, efficiently merging enamines and (unactivated) alkynes under oxidative conditions. In an intermolecular Rh catalyzed process, the challenging allylic sp3 C-H activation of the enamine substrates is followed by the cyclization with the alkyne (R3 = CO2R). Alternatively, in some cases (R 3 = CN), the enamine can be utilized for a vinylic sp2 C-H activation. A total of 17 examples with yields above 60% is presented, together with the results of an initial mechanistic investigation.
Iridium-catalyzed hydrogenation of β-dehydroamino acid derivatives using monodentate phosphoramidites
Enthaler, Stephan,Erre, Giulia,Junge, Kathrin,Schroeder, Kristin,Addis, Daniele,Michalik, Dirk,Hapke, Marko,Redkin, Dmitry,Beller, Matthias
experimental part, p. 3352 - 3362 (2009/04/07)
The iridium-catalyzed asymmetric hydrogenation of 13 different β-dehydroamino acid derivatives to give optically active β-amino acid esters has been examined. Readily accessible monodentate octahydrobinaphthol- based phosphoramidites were used as chiral ligands. Good to excellent enantioselectivities and yields were obtained for the E isomers, whereas poorer catalyst performance was found for the Z isomers. Importantly, to obtain high enantioselectivity, substitution at the 3,3′-positions of the ligands was necessary. Enantioselectivities of up to 94% ee were achieved under optimized conditions. Wiley-VCH Verlag GmbH & Co. KGaA, 2008.
Development of practical rhodium phosphine catalysts for the hydrogenation of β-dehydroamino acid derivatives
Enthaler, Stephan,Erre, Giulia,Junge, Kathrin,Holz, Jens,Boerner, Armin,Alberico, Elisabetta,Nieddu, Ilenia,Gladiali, Serafino,Beller, Matthias
, p. 568 - 577 (2012/12/31)
The rhodium-catalyzed asymmetric hydrogenation of various β-dehydroamino acid derivatives to give optically active β-amino acids has been examined. Chiral monodentate 4,5-dihydro-3H-dinaphthophosphepines, which are easily tuned and accessible in a multi-10-g scale, have been used as ligands. The enantioselectivity is largely dependent on the nature of the substituent at the phosphorous atom and on the structure of the substrate. Applying optimized conditions up to 94% ee was achieved.
Copper-catalyzed coupling of amides and carbamates with vinyl halides
Jiang, Lei,Job, Gabriel E.,Klapars, Artis,Buchwald, Stephen L.
, p. 3667 - 3669 (2007/10/03)
(Matrix presented) A general and efficient copper-catalyzed method for the amidation of vinyl bromides and iodides has been developed. This protocol uses a combination of 5 mol % copper iodide and 20 mol % N,N′-dimethyl ethylenediamine. Substrates bearing ester, silyl ether, and amino groups were successfully coupled under the reaction conditions. The double bond geometry of the vinyl halides was retained under the reaction conditions.
