5344-60-5Relevant academic research and scientific papers
Photoinduced Deaminative Alkylation for the Synthesis of γ-Ketoesters via Electron Donor–Acceptor Complex Formation
Wang, Jia-Xin,Ge, Wei,Xing, Wei-Long,Fu, Ming-Chen
, p. 18224 - 18231 (2021/12/13)
Visible-light-induced deaminative alkylation of Katritzky salts with silyl enol ethers has been developed. The reaction can proceed efficiently through electron donor–acceptor complex formation, avoiding the use of precious metal complexes or synthetically elaborate organic dyes. A series of functionalized γ-ketoesters was successfully obtained with good functional group tolerance and compatibility under mild and straightforward conditions.
Visible-Light-Promoted Polysubstituted Olefins Synthesis Involving Sulfur Ylides as Carbene Trapping Reagents
Ye, Cong,Cai, Bao-Gui,Lu, Juan,Cheng, Xiao,Li, Lei,Pan, Zhong-Wen,Xuan, Jun
, p. 1012 - 1022 (2021/01/09)
A blue-light-emitting diode (LED) promoted coupling of aryl diazoacetates with sulfur ylides is described. This protocol features mild conditions, good functional group tolerance, and broad substrate scope for both aryl diazoacetates with sulfur ylides. Under optimal reaction conditions, a wide range of trisubstituted olefins is obtained in moderate to good yield, which can be further transferred to other biologically important heterocycles after a two-step simple operation.
Photocatalytic Hydromethylation and Hydroalkylation of Olefins Enabled by Titanium Dioxide Mediated Decarboxylation
Zhu, Qilei,Nocera, Daniel G.
, p. 17913 - 17918 (2020/12/04)
A versatile method for the hydromethylation and hydroalkylation of alkenes at room temperature is achieved by using the photooxidative redox capacity of the valence band of anatase titanium dioxide (TiO2). Mechanistic studies support a radical-based mechanism involving the photoexcitation of TiO2 with 390 nm light in the presence of acetic acid and other carboxylic acids to generate methyl and alkyl radicals, respectively, without the need for stoichiometric base. This protocol is accepting of a broad scope of alkene and carboxylic acids, including challenging ones that produce highly reactive primary alkyl radicals and those containing functional groups that are susceptible to nucleophilic substitution such as alkyl halides. This methodology highlights the utility of using heterogeneous semiconductor photocatalysts such as TiO2 for promoting challenging organic syntheses that rely on highly reactive intermediates.
Benzothiazolines as radical transfer reagents: Hydroalkylation and hydroacylation of alkenes by radical generation under photoirradiation conditions
Uchikura, Tatsuhiro,Moriyama, Kaworuko,Toda, Mitsuhiro,Mouri, Toshiki,Ibá?ez, Ignacio,Akiyama, Takahiko
, p. 11171 - 11174 (2019/09/30)
Novel radical transfer reagents under photoirradiation conditions were developed by the use of benzothiazoline derivatives. These reagents enabled both hydroalkylation and hydroacylation of alkenes under neutral conditions at ambient temperature without a
One-Pot Quinine-Catalyzed Synthesis of α-Chiral γ-Keto Esters: Enantioenriched Precursors of cis-α,γ-Substituted-γ-Butyrolactones
Meninno, Sara,Volpe, Chiara,Lattanzi, Alessandra
supporting information, p. 2845 - 2848 (2016/09/13)
A highly enantioselective one-pot synthesis of important building blocks, α-chiral γ-keto esters, has been developed by combining a quinine-catalyzed Michael addition of malononitrile to trans-enones followed by magnesium monoperoxyphthalate (MMPP) oxidat
Copper-Catalyzed Coupling of 2-Siloxy-1-alkenes and Diazocarbonyl Compounds: Approach to Multisubstituted Furans, Pyrroles, and Thiophenes
Tan, Wei Wen,Yoshikai, Naohiko
, p. 5566 - 5573 (2016/07/14)
We report herein copper(II)-catalyzed cyclization reactions of silyl enol ethers derived from methyl ketones with α-diazo-β-ketoesters or α-diazoketones to afford 2-siloxy-2,3-dihydrofuran derivatives or 2,3,5-trisubstituted furans, respectively, under mild conditions. The former cyclization products serve as versatile 1,4-diketone surrogates, allowing facile preparation of 2,3,5-trisubstituted furans, pyrroles, and thiophenes.
Formation of five-membered cyclic orthoesters from tribromides with participation of a neighboring carbonyl group
Gururaja, Guddeangadi N.,Mobin, Shaikh M.,Namboothiri, Irishi N. N.
experimental part, p. 2048 - 2052 (2011/05/16)
The Mg-mediated conjugate addition of bromoform to enones followed by alcoholysis of the resulting keto tribromides proceeds through an unusual course, affording cyclic orthoester (dihydrofuran) intermediates under neutral workup conditions. However, acid
Malononitrile as acylanion equivalent
F?rster, Sebastian,Tverskoy, Olena,Helmchen, Günter
experimental part, p. 2803 - 2806 (2009/05/26)
The oxidation of derivatives of malononitrile with peracid in methanol proceeds with loss of the cyano groups to yield methyl esters in high yield. The method was applied to a variety of malononitrile derivatives, some of which were prepared by Pd- or Ir-catalyzed asymmetric allylic substitution. Georg Thieme Verlag Stuttgart.
New reaction of enamines with aryldiazoacetates catalyzed by transition metal complexes
Zhao, Wei-Jie,Yan, Ming,Huang, Dan,Ji, Shun-Jun
, p. 5585 - 5593 (2007/10/03)
The reaction of aryldiazoacetates with enamines catalyzed by copper and rhodium complexes provided γ-keto esters in good yields. A full investigation of the effects of solvents, catalysts, enamines and aryldiazoacetates on the reaction was carried out. Careful analysis of the crude reaction mixture revealed a substituted enamine as the primary product, which was hydrolyzed over silica gel to give a γ-keto ester as the final product. A reaction mechanism involving nucleophilic addition of an enamine to a metal carbene and subsequent hydrogen transfer was proposed. Chiral dirhodium and copper catalysts were examined and found to provide γ-keto esters with no enantioselectivity. The result could be rationalized based on the proposed reaction mechanism. Attempts to trap the enamine intermediate with several electrophilic reagents were not successful.
Microwave assisted synthesis of 4,6-diarylpyridazin-3(2H)-ones in solid state
Meenakshi,Ramamoorthy,Muthusubramanian,Sivasubramanian
, p. 645 - 651 (2007/10/03)
Microwave assisted synthesis of dihydropyridazin-3(2H)-ones and the subsequent dehydrogenation using selenium dioxide are described.
