38661-88-0Relevant academic research and scientific papers
Stereospecific Decarboxylative Nazarov Cyclization Mediated by Carbon Dioxide for the Preparation of Highly Substituted 2-Cyclopentenones
Komatsuki, Keiichi,Sadamitsu, Yuta,Sekine, Kohei,Saito, Kodai,Yamada, Tohru
, p. 11594 - 11598 (2017/09/11)
Highly substituted 2-cyclopentenones were stereospecifically and regioselectively constructed with high catalytic efficiency through Lewis-acid catalyzed decarboxylative Nazarov cyclization of the cyclic carbonate derivative, which is prepared by reacting the propargyl alcohol with carbon dioxide in the presence of a silver catalyst. The stereochemistry of the 2-cyclopentenone is strictly controlled by the geometry of the alkene in the starting material. This method is applicable for various substrates.
Acid-catalyzed synthesis of α,β-disubstituted conjugated enones by a Meyer-Schuster-type rearrangement in allenols
Alcaide, Benito,Almendros, Pedro,Cembellín, Sara,Martínez Del Campo, Teresa
, p. 1070 - 1078 (2015/03/30)
A novel, direct and simple methodology to gain access to α,β-disubstituted conjugated enones from α-allenols in a sustainable metal catalysis context, considering the inexpensiveness and environmentally friendliness of iron(III) species and protons, has b
Copper-catalyzed regio- and stereoselective intermolecular three-component oxyarylation of allenes
Itoh, Taisuke,Shimizu, Yohei,Kanai, Motomu
supporting information, p. 2736 - 2739 (2014/06/09)
A copper(II)-catalyzed intermolecular three-component oxyarylation of allenes using arylboronic acids as a carbon source and TEMPO as an oxygen source is described. The reaction proceeded under mild conditions with high regio- and stereoselectivity and functional group tolerance. A plausible reaction mechanism is proposed, involving carbocupration of allenes, homolysis of the intervening allylcopper(II), and a radical TEMPO trap.
Synthesis and antimicrobial evaluation of some pyrazole derivatives
Sharshira, Essam Mohamed,Hamada, Nagwa Mohamed Mahrous
scheme or table, p. 4962 - 4971 (2012/09/22)
Reaction of a series of (E)-3-phenyl-4-(p-substituted phenyl)-3-buten-2- ones with p-sulfamylphenyl hydrazine in glacial acetic acid gave the corresponding hydrazones, subsequent treatment of which with 30% HCl afforded pyrazole-1-sulphonamides. On the ot
Iridium-catalyzed asymmetric hydrogenation of α-substituted α,β-unsaturated acyclic ketones: Enantioselective total synthesis of (-)-mesembrine
Zhang, Qian-Qian,Xie, Jian-Hua,Yang, Xiao-Hui,Xie, Jian-Bo,Zhou, Qi-Lin
supporting information, p. 6158 - 6161 (2013/02/23)
A highly efficient asymmetric hydrogenation of α-substituted α,β-unsaturated acyclic ketones catalyzed by chiral spiro iridium complexes for the preparation of chiral 2-substituted allylic alcohols has been developed (ee up to 99.7%). This method provides a concise route to (-)-mesembrine (34% yield, 12 steps).
Palladium-catalyzed oxidative cross-coupling reaction of arylboronic acids with diazoesters for stereoselective synthesis of (E)-α,β- diarylacrylates
Tsoi, Yuk-Tai,Zhou, Zhongyuan,Chan, Albert S. C.,Yu, Wing-Yiu
supporting information; experimental part, p. 4506 - 4509 (2010/12/25)
A Pd-catalyzed oxidative cross-coupling reaction of arylboronic acids with α-diazoesters was achieved using molecular oxygen as the sole reoxidant, and E-α,β-diarylacrylates were obtained in good yields and >20:1 E-to-Z selectivity.
CuH-catalyzed enantioselective 1,2-reductions of α,β-unsaturated ketones
Moser, Ralph,Boskovia, Zarko V.,Crowe, Christopher S.,Lipshutz, Bruce H.
supporting information; experimental part, p. 7852 - 7853 (2010/08/04)
The first study on a general technology for arriving at valued nonracemic allylic alcohols using asymmetric ligand-accelerated catalysis by copper hydride is described.
A nonsymmetric pincer-catalyzed Suzuki-Miyaura arylation of benzyl halides and other nonactivated unusual coupling partners
Ines, Blanca,Moreno, Isabel,SanMartin, Raul,Dominguez, Esther
supporting information; experimental part, p. 8448 - 8451 (2009/04/11)
(Chemical Equation Presented) The catalytic activity of a PCN-type palladium pincer complex is evaluated in the construction of C(sp 2)-C(sp2) and C(sp2)-C(sp3) bonds by Suzuki-Miyaura cross-couplings employing nontypical substrates such as benzyl halides, α-haloenones, or alkylboronic acids as coupling partners. Most of the reported reactions are achieved in aqueous media, with all of the advantages implied.
Highly enantioselective synthesis of optically active ketones by iridium-catalyzed asymmetric hydrogenation
Lu, Sheng-Mei,Bolm, Carsten
supporting information; experimental part, p. 8920 - 8923 (2009/05/30)
(Chemical Equation Presented) Close to perfect enantioselectivity (up to 99% ee, see scheme) is found for the formation of α-substituted ketones by the asymmetric hydrogenation of enones with an iridium-phosphinooxazoline catalyst. In an operationally simple process, both linear and cyclic substrates react well and afford the desired products in high yields. A wide variety of substituents are tolerated, thus making the method synthetically appealing.
The α-arylation of α-bromo- and α-chloroenones using palladium-catalysed cross-coupling
Banks, James C.,Mele, David Van,Frost, Christopher G.
, p. 2863 - 2866 (2007/10/03)
The palladium-catalysed cross-coupling reaction of various arylboronic acids with α-bromoenones and α-chloroenones offers an operationally simple approach to the synthesis of both cyclic and acyclic α-arylenones.
