30085-70-2Relevant articles and documents
Reversal of diastereoselectivity in reactions of the trifluoroacetaldehyde ethyl hemiacetal with enamines and imines: Metal-free, complementary anti-and syn-selective synthesis of 4,4,4-trifluoro-1-aryl-3-hydroxy-2-methyl-1-butanones
Funabiki, Kazumasa,Matsunaga, Kei,Gonda, Hiroshi,Yamamoto, Hitoshi,Arima, Takao,Kubota, Yasuhiro,Matsui, Masaki
, p. 285 - 288 (2011)
A complete reversal of diastereoselectivity was observed for reactions of the trifluoroacetaldehyde ethyl hemiacetal with enamines and imines, derived from propiophenones, that produce 4,4,4-trifluoro-1-aryl-3-hydroxy-2-methyl-1- butanones. This process s
Achieving Aliphatic Amine Addition to Arylalkynes via the Lewis Acid Assisted Triazole-Gold (TA-Au) Catalyst System
Jia, Teng,Fan, Shengyu,Li, Fengmian,Ye, Xiaohan,Zhang, Wenke,Song, Zhiguang,Shi, Xiaodong
supporting information, p. 6019 - 6023 (2021/08/03)
Transition metal catalyzed intermolecular hydroamination of the arylalkynes with aliphatic amine is generally problematic due to the good coordination between amine and metal cation. With the combination of 1,2,3-triazole coordinated gold(I) catalyst (TA-Au) and Zn(OTf)2 cocatalyst, this challenging transformation was achieved with good to excellent yields and regioselectivity. Compared to previously reported methods, this approach offered an alternative catalyst system to achieve this fundamental chemical transformation with high efficiency and practical conditions.
Highly diastereo- and enantioselective copper-catalyzed propargylic alkylation of acyclic ketone enamines for the construction of two vicinal stereocenters
Zhang, De-Yang,Zhu, Fu-Lin,Wang, Ya-Hui,Hu, Xin-Hu,Chen, Song,Hou, Chuan-Jin,Hu, Xiang-Ping
supporting information, p. 14459 - 14462 (2015/02/19)
The first highly diastereo- and enantioselective propargylic alkylation of acyclic ketone enamines to form vicinal tertiary stereocenters has been reported by employing copper catalysis in combination with a bulky and structurally rigid tridentate ketimine P,N,N-ligand.
N -(4-cyanotetrahydro-2 H -pyran-4-yl) and N -(1-cyanocyclohexyl) derivatives of 1,5-diarylpyrazole-3-carboxamides showing high affinity for 18 kDa translocator protein and/or cannabinoid receptors
Donohue, Sean R.,Dannals, Robert F.,Halldin, Christer,Pike, Victor W.
experimental part, p. 2961 - 2970 (2011/06/24)
In order to develop improved radioligands for imaging brain CB1 receptors with positron emission tomography (PET) based on rimonabant (5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methyl-N-(piperidin-1-yl) -1H-pyrazole-3-carboxamide, 1), we synt
Reactions of enamines with selectfluor: A straightforward route to difluorinated carbonyl compounds
Peng, Weimin,Shreeve, Jean'ne M.
, p. 5760 - 5763 (2007/10/03)
Reactions of enamines, preformed from β-dicarbonyl and monocarbonyl compounds, with Selectfluor (1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2] octane bis(tetrafluoroborate) under mild conditions (triethylamine (TEA) or molecular sieves) easily led to the corresponding difluorinated carbonyl compounds in high yields.
178. Stereoselectivity of the Radical Reductive Alkylation of Enamines: Importance of the Allylic 1,3-Strain Model
Schubert, Serge,Renaud, Philippe,Carrupt, Pierre-Alain,Schenk, Kurt
, p. 2473 - 2489 (2007/10/02)
Radical addition to enamines using Bu3SnH as reducing agent are reported (Schemes 2 and 4).The diastereoselectivity of these reactions was examined in different systems (Tables 1 and 2).Enamines derived from cyclic ketones such as cyclohexanone were alkyl
Studies on the Oxidation of Enamines with Molecular Oxygen. III Oxidation of Some Amino Styrenes
Blau, K.,Burgemeister, I.,Grasnick, J.,Voerckel, V.
, p. 455 - 466 (2007/10/02)
In the oxidation of the amino styrenes 1a - 1j only products of the oxidative attack at the C=C double bond and hydrolysis products are obtained.Aprotic dipolar solvents and the addition of molecular sieve 5A promote the oxygen uptake.The addition of hydroquinone to the oxidation system does not influence the rate of oxygen absorption or the yields of the oxidation products.
New Methods and Reagents in Organic Synthesis. 34. Diphenyl Phosphorazidate (DPPA) as a 1,3-Dipole. A Simple, Efficient Conversion of Alkyl Phenyl Ketones to 2-Phenylalkanoic Acids
Kawai, Nobutaka,Shioiri, Takayuki
, p. 2564 - 2573 (2007/10/02)
Propiophenone (11) was conveniently converted to its enamines 12a-c using boron trifluoride etherate as a catalyst.Reaction of diphenyl phosphorazidate (DPPA) with the enamines 12a-c efficiently afforded the N-phosphorylated amidines 14a-c by the 1,3-dipolar cycloaddition of DPPA to the enamine double bond, followed by the evolution of nitrogen from the intermediate triazoline 13, and 1,2-migration of the phenyl group. 1,3-Dipolar elimination products 15a-c were also formed, though in very low yields.Some chemical properties of the N-phosphorylated amidine 14a, as well as the 1,3-dipolar character of DPPA, were investigated.By the same reaction sequences (enamine formation followed by the 1,3-dipolar cycloaddition of DPPA), some alkyl phenyl ketones 29a-c were conveniently converted to the N-phosphorylated amidines 31a, 31b, and 27 via the enamines 30a-c.However , in the case of acetophenone and its derivatives 33a-c, these reaction sequences proceeded sluggishly.Alkaline hydrolysis of the N-phosphorylated amidines 14a, 31a, 31b and 27 with potassium hydroxide afforded 2-phenylalkanoic acids 25 and 32a-c, respectively, in excellent yields.The overall three-step process of successive treatment of alkyl phenyl ketones (alkylmethyl) with pyrrolidine, DPPA, and potassium hydroxide may provide a new general method for the efficient conversion of alkyl aryl ketones to 2-arylalkanoic acids.Keywords - enamine; diphenyl phosphorazidate; boron trifluoride etherate; 1,3-dipolar cycloaddition; 1,2-migration; N-phosphorylated amidine; alkaline hydrolysis; alkyl aryl ketone; 2-arylalkanoic acid
