- From Simple Cyclic 1,3-Ketoamides to Complex Spirolactams by Supported Heterogeneous Organocatalysis with PS-BEMP
-
The reaction between cyclic 1,3-ketoamides and Michael acceptors in the presence of a catalytic amount of a polymer-supported organobase PS-BEMP has been developed for a direct access to spirocyclic 1,3-ketolactams through a domino Michael addition/hemiac
- Benmaati, Aouicha,Zahmani, Hadjira Habib,Hacini, Salih,Menéndez, José Carlos,Bugaut, Xavier,Rodriguez, Jean,Constantieux, Thierry
-
-
Read Online
- Highly Selective Difluoromethylations of β-Keto Amides with -TMSCF 2Br under Mild Conditions
-
Without employing any transition metal and other additives, efficient methods for selective difluoromethylations of β-keto amides with TMSCF 2 Br reagent have been developed under mild conditions. This protocol allows a convenient access to various α-difluoromethyl β-keto amides with excellent yields (up to 93%) and high carbon/oxygen (C/O) regioselectivities (up to 99:1). The C/O selectivity of β-keto amides could be easily reversed and controlled by simply changing the base. This protocol can be easily scaled-up and the C-difluoromethylation product could be reduced into CF 2 H-containing amino alcohol derivatives. Moreover, the first enantioselective electrophilic difluoromethylation of β-keto amides has been achieved by phase-transfer catalysis.
- Chen, Pengli,Fu, Yang,Hu, Yanqin,Wang, Shuaifei,Wang, Yakun,Zhang, Conghui,Zhang, Mingwei,Zhao, Ting
-
p. 1123 - 1130
(2021/06/18)
-
- Identification of new biologically active synthetic molecules: comparative experimental and theoretical studies on the structure-antioxidant activity relationship of cyclic 1,3-ketoamides
-
Antioxidant agent is a chemical that prevents the oxidation of other chemical substances. Its use is the most effective means of protecting the organism by neutralizing the harmful effects of free radicals caused by oxidative stress. In the present work, a series of β-ketoamides containing a variety of monosubstituted amide groups were synthesized and tested as antioxidant agents. In order to establish a possible structure-antioxidant activity relationship, we are presenting a systematic theoretical study of these molecules with the aim of clarifying the active sites. In particular, we discuss the selectivity resulting from the choice of a free radical/antioxidant system. The theoretical study of these molecules was carried out using density functional theory (DFT) calculations at the B3LYP/6-311G (d,p) level of theory. In order to shed light on the antioxidant properties of β-ketoamides, O–H bond dissociation enthalpies (BDEs), ionization potentials (IPs), electron affinities (EAs), proton affinities (PAs), and electron transfer enthalpies (ETEs) are performed in the gas phase and in ethanol. The results obtained show that the HAT mechanism is thermodynamically more favored in the gas phase, while the SPLET is preferred in the polar solvent.
- Kerbadou, Riad Mustapha,Hadjadj Aoul, Ratiba,Benmaati, Aouicha,Taleb, Assya,Hacini, Salih,Habib Zahmani, Hadjira
-
-
- A Chiral Phenanthroline Ligand with a Hydrogen-Bonding Site: Application to the Enantioselective Amination of Methylene Groups
-
A silver-catalyzed amination is reported that occurs at the aliphatic C3-substituent of various quinolones and pyridones. The C-H amination reaction proceeded with high site-and enantioselectivity (14 examples, 83-97% ee). The key to its success is the use of a chiral phenanthroline ligand that is attached via an ethynyl linker to the 8-position of octahydro-1H-4,7-methanoisoindol-1-one. AgPF6 (10 mol %) served as the silver source, PhI.NNs as the nitrene precursor, and 1,10-phenanthroline as the coligand. The reaction outcome can be understood by assuming a nitrene C-H insertion within a hydrogen-bonded silver complex in which a single C-H bond is exposed to the catalytic reaction center.
- Annapureddy, Rajasekar Reddy,Jandl, Christian,Bach, Thorsten
-
supporting information
p. 7374 - 7378
(2020/08/06)
-
- Eco-friendly access to β-ketoamides: One-step catalyst-and solvent-free amidation of β-ketoesters under microwave irradiation
-
A highly efficient and facile catalyst- and solvent-free one step amidation of β-ketoesters, without using any additional reagents, is described. Therefore, β-ketoamides are obtained in good to excellent yields by condensation of β-ketoesters with various primary or secondary amines. This eco-friendly protocol has been developed under microwave irradiation.
- Dechira, Khadidja,Taleb, Assya,Benmaati, Aouicha,Hacini, Salih,Zahmani, Hadjira Habib
-
p. 152 - 160
(2018/03/21)
-
- Usual and unusual reactions of cyclohexane-1,2-dione with aryl azides and amines: a structural corrigendum
-
The reported syntheses of alleged functionalised 1,2,3-triazines from cyclohexane-1,2-dione and aryl azides, in the presence of pyrrolidine and other amines, were repeated. The products do not contain the bicyclic triazine and bicyclic ketone moieties; instead, cyclohexane-fused 4,5-dihydro-1,2,3-triazoles and monocyclic β-ketoamides were obtained, respectively. These corrections are well supported by careful analyses of NMR spectra, IR spectra, elemental analysis and comparison with data which were previously published in the literature. Suitable mechanisms are discussed for the synthesis of the observed compounds.
- Singh, Neeraj,Banert, Klaus
-
supporting information
p. 1897 - 1901
(2017/03/09)
-
- Unique features of chiral palladium enolates derived from β-ketoamide: structure and catalytic asymmetric Michael and fluorination reactions
-
Abstract We have previously reported enantioselective reactions of 1,3-diketones and β-ketoesters with various electrophiles catalyzed by chiral Pd complex, in which chiral Pd enolates play a key role. Here, we present a detailed examination of Pd-catalyz
- Hayamizu, Kenji,Terayama, Naoki,Hashizume, Daisuke,Dodo, Kosuke,Sodeoka, Mikiko
-
supporting information
p. 6594 - 6601
(2015/08/18)
-
- Enantioselective fluorination of β-ketoamides catalyzed by Ar-BINMOL-derived salan-copper complex
-
A facile and powerful enantioselective construction of C-F containing molecules was successfully developed through asymmetric fluorination of β-ketoamides catalyzed by Ar-BINMOL-derived salan-CuII system (Ar-BINMOL=1,1'-Binaphthalene-2-α-arylmethanol-2'-ol, Cu = copper). The present catalytic system exhibited excellent enantioselectivity and a broad substrate scope for indanone-derived β-ketoamides under mild conditions (up to 99% ee and 99% yields). Notably, the biomimetic salan-copper complex was demonstrated for the first time to be a highly efficient catalyst in the fluorination of β-ketoamides. Experimental results and mechanistic studies indicated that both excess amount of copper salt and electrophilic attack of cationic fluorine to activated methylene assisted by amide group on the β-ketoamides were key factors for high yield and excellent enantioselectivity, respectively, in this enantioselective fluorination, which was controlled by the two-point binding between the salan-copper complex with cyclic β-ketoamides and hydrogen-bonding activation of the electrophilic fluorinating reagent.
- Zheng, Long-Sheng,Wei, Yun-Long,Jiang, Ke-Zhi,Deng, Yuan,Zheng, Zhan-Jiang,Xu, Li-Wen
-
supporting information
p. 3769 - 3776
(2015/03/04)
-
- Microwave-assisted wolff rearrangement of cyclic 2-diazo-1,3-diketones: An eco-compatible route to α-carbonylated cycloalkanones
-
(Chemical Equation Presented) The microwave-assisted Wolff rearrangement of cyclic 2-diazo-1,3-diketones performed in the presence of a stoichiometric amount of alcohol, amine, or thiol is an efficient, user, and environmentally friendly synthetic protocol for the synthesis of α-carbonylated cycloalkanones. This approach proves superior to existing protocols in scope and eco-compatibility.
- Presset, Marc,Coquerel, Yoann,Rodriguez, Jean
-
supporting information; experimental part
p. 415 - 418
(2009/04/10)
-
- Dihydroquinolines as novel n-NOS inhibitors
-
Dihydroquinolines have been synthesized and have been shown to be potent n-NOS inhibitors. Selectivity versus e-NOS was increased to approximately 100-fold through appropriate substitution at the benzene ring.
- Jaroch, Stefan,Hoelscher, Peter,Rehwinkel, Hartmut,Suelzle, Detlev,Burton, Gerardine,Hillmann, Margrit,McDonald, Fiona M.
-
p. 2561 - 2564
(2007/10/03)
-
- 4-Alkyl- and 3,4-dialkyl-1,2,3,4-tetrahydro-8-pyridono[5,6- g]quinolines: Potent, nonsteroidal androgen receptor agonists
-
A series of human androgen receptor (hAR) agonists based on 4-alkyl-; 4,4-dialkyl-; and 3,4-dialkyl-1,2,3,4-tetrahydro-8-pyridono[5,6-g]quinoline was synthesized and evaluated in competitive receptor binding assays and an androgen receptor cotransfection assay in a mammalian cell background. A number of compounds in this series demonstrated activity equal to or better than dihydrotestosterone in both assays and represent a novel class of compounds for use in androgen replacement therapy.
- Higuchi, Robert I.,Edwards, James P.,Caferro, Thomas R.,Ringgenberg, Josef D.,Kong, James W.,Hamann, Lawrence G.,Arienti, Kristen L.,Marschke, Keith B.,Davis, Robert L.,Farmer, Luc J.,Jones, Todd K.
-
p. 1335 - 1340
(2007/10/03)
-
- New arylpiperazine derivatives with high affinity for 5-HT3 receptor sites
-
The synthesis and 5-HT3 affinities of 3- and 4-substituted -2-(1-piperazinyl) or -(4-methyl-1-piperazinyl)quinoline are reported. These compounds display higher affinities than derivatives from the same chemical family, such as quipazine or 7-(
- Castan, Florence,Schambel, Philippe,Enrici, Agnes,Rolland, Francoise,Bigg, Dennis C. H.
-
-
- Enamine Chemistry. XVII. Reduction of Enaminones, Enaminothiones and Thioamides by LiAlH4 and NaBH4
-
Enamines, 1, prepared from cycloalkanones, (cyclopentanone and cyclohexanone), and secondary amines (pyrrolidine, piperidine and morpholine), are reacted with phenylisocyanate and phenylisothiocyanate to give inseparable mixtures of enaminones (enaminothi
- Ghattas, A.-B.A.G.,Jorgensen, K. A.,Lawesson, S.-O.
-
p. 505 - 512
(2007/10/02)
-