51787-96-3Relevant academic research and scientific papers
Efficient hydrogenation of levulinic acid catalysed by spherical NHC-Ir assemblies with atmospheric pressure of hydrogen
Liu, Yaoqi,Lu, Zeye,Shen, Lingyun,Tu, Tao,Wu, Jiajie,Zheng, Qingshu
supporting information, p. 5037 - 5042 (2021/07/29)
A practical, efficient, and mild hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) under 1 atm H2was realized by single-sited 3D porous self-supported N-heterocyclic carbene iridium catalysts. Quantitative yields and selectivities were achieved at 0.02 mol% catalyst loading, and the catalyst could be reused for 9 runs without obvious loss of selectivity or activity.
Biocatalytic Asymmetric Reduction of γ-Keto Esters to Access Optically Active γ-Aryl-γ-butyrolactones
??d?o-Dobrowolska, Anna,Borowiecki, Pawe?,Heider, Johann,Kroutil, Wolfgang,Reiter, Tamara,Schühle, Karola,Szaleniec, Maciej,Tataruch, Mateusz,Telatycka, Natalia
, (2020/04/20)
An efficient stereoselective syntheses of a series of functionalized optically active γ-aryl-γ-butyrolactones is achieved by enzymatic asymmetric reduction of the corresponding sterically demanding γ-keto esters employing wild-type and recombinant alcohol dehydrogenases. The best stereoselectivities for the reduction via hydrogen transfer was obtained with two short chain dehydrogenases (SDRs) of complementary stereospecificity from Aromatoleum aromaticum, namely the Prelog-specific NADH-dependent (S)-1-phenylethanol dehydrogenase [(S)-PED] and the anti-Prelog-specific (R)-1-(4-hydroxyphenyl)-ethanol dehydrogenase [(R)-HPED], respectively.Biotransformations catalyzed by both enzymes, followed by TFA-catalyzed cyclization of the resulting γ-hydroxy esters, furnished the respective (S)- and (R)-configured products with exquisite optical purity (up to >99% ee). The synthetic value was demonstrated on preparative scale for the asymmetric bioreduction of the model compound, methyl 4-oxo-4-phenylbutanoate, affording optically pure (S)-γ-phenyl-γ-butyrolactone (>99% ee) in 67–74% isolated yield at 89–95% conversion depending on the applied scale. (Figure presented.).
Synthesis of chiral γ-lactones via a RuPHOX-Ru catalyzed asymmetric hydrogenation of aroylacrylic acids
Lu, Yufei,Li, Jing,Zhu, Yue,Shen, Jiefeng,Liu, Delong,Zhang, Wanbin
, p. 3643 - 3649 (2019/05/29)
An asymmetric hydrogenation of aroylacrylic acids catalyzed by RuPHOX-Ru catalyst has been developed, affording the corresponding chiral γ-lactones in high yields and with up to 93% ee. The methodology has the advantage of utilizing easily accessible substrates and has therefore expand the scope of the resulting chiral γ-lactones. Furthermore, high catalytic efficiency was achieved in that the reduction of both the C[dbnd]C and C[dbnd]O double bonds was achieved in one step. The current work provides an alternative and convenient pathway for the synthesis of a wide range of chiral γ-lactones.
Cooperative iodine and photoredox catalysis for direct oxidative lactonization of carboxylic acids
Duhamel, Thomas,Mu?iz, Kilian
supporting information, p. 933 - 936 (2019/01/23)
A new method for the formation of γ- and δ-lactones from carboxylic acids through direct conversion of benzylic C-H to C-O bonds is described. The reaction is conveniently induced by visible light and relies on a mild cooperative catalysis by the combination of molecular iodine and an organic dye.
Synthesis of Enantiopure γ-Lactones via a RuPHOX-Ru Catalyzed Asymmetric Hydrogenation of γ-Keto Acids
Li, Jing,Ma, Yujie,Lu, Yufei,Liu, Yangang,Liu, Delong,Zhang, Wanbin
, p. 1146 - 1153 (2019/01/30)
A RuPHOX?Ru catalyzed asymmetric hydrogenation of γ-keto acids has been developed, affording the corresponding enantiopure γ-lactones in high yields and with up to 97% ee. The reaction could be performed on a gram scale with a relatively low catalyst loading (up to 10000 S/C) under the indicated reaction conditions and the resulting products can be transformed to several enantiopure building blocks, biologically active compounds and enantiopure drugs. (Figure presented.).
Indium-Catalyzed Direct Conversion of Lactones into Thiolactones and Selenolactones in the Presence of Elemental Sulfur and Selenium
Sakai, Norio,Horikawa, Shuhei,Ogiwara, Yohei
, p. 565 - 574 (2017/12/26)
The direct conversion of lactones into thiolactones with elemental sulfur (S 8) catalyzed by InCl 3 /PhSiH 3 in a one-pot reaction is described. This catalytic system was successfully applied to the novel preparation of selenolactones from lactones and selenium.
Nucleo-Palladation-Triggering Alkene Functionalization: A Route to γ-Lactones
Zheng, Meifang,Chen, Pengquan,Huang, Liangbin,Wu, Wanqing,Jiang, Huanfeng
supporting information, p. 5756 - 5759 (2017/11/10)
An unprecedented strategy for the highly effective synthesis of γ-lactones from homoallylic alcohols was achieved by palladium catalysis in one step. The protocol affords aryl, alkyl, and spiro γ-lactones directly from readily available homoallylic alcohols in good yields with excellent functional group tolerance and high chemoselectivity under mild conditions.
Electroreductive coupling of aromatic ketones, aldehydes, and aldimines with α,β-unsaturated esters: Synthesis of 5-aryl substituted γ-butyrolactones and lactams
Kise, Naoki,Hamada, Yusuke,Sakurai, Toshihiko
, p. 1143 - 1156 (2017/02/18)
The electroreductive intermolecular coupling of aromatic ketones and aldehydes with α,β-unsaturated esters in the presence of TMSCl gave the adducts as γ-trimethylsiloxy esters. The detrimethylsilylation of the adducts with TBAF afforded 5-aryl substituted γ-butyrolactones. The electroreductive coupling of N-(4-methoxyphenyl)-1-arylmethaneimines with methyl acrylate in the presence of TMSCl gave the adducts as methyl 4-aryl-4-((4-methoxyphenyl)amino)butanoates. The adducts were transformed to 5-aryl-γ-butyrolactams by cyclization with NaH and subsequent oxidation with CAN. (±)-Norcotinine was prepared from nicotinaldehyde by this method. The electroreductive coupling of aromatic ketones and aldimines with acrylonitrile in the presence of TMSCl gave 4-aryl-4-(trimethylsiloxy)butanenitriles and 4-aryl-4-((4-methoxyphenyl)amino)butanenitriles, respectively.
Efficient Hydrogenation of Biomass Oxoacids to Lactones by Using NHC–Iridium Coordination Polymers as Solid Molecular Catalysts
Liu, Yaoqi,Sun, Zheming,Huang, Changyu,Tu, Tao
, p. 355 - 360 (2017/02/05)
A series of NHC–iridium coordination polymers have proven to be robust, efficient and recyclable solid molecular catalysts toward the hydrogenation of biomass levulinic acid (LA) to γ-valerolactone. Along with quantitative yields attained at 0.01 mol % catalyst loading under 50 atm of H2, the solid molecular catalyst was readily recovered and reused for 12 runs without obvious loss of the selectivity and activity. Remarkably, up to 1.2×105 TON, an unprecedented value could be achieved in this important transformation. In addition, a number of LA homologues, analogues and derivatives were well tolerated to deliver various intriguing and functional lactones in good to excellent yields, which further confirmed the feasibility of the solid molecular catalysts.
Penfluridol preparation method
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, (2017/02/24)
The invention discloses a penfluridol preparation method. The penfluridol preparation method includes the following steps of 1), subjecting succinic anhydride and fluorobenzene to Friedel-Crafts reaction prior to acid decomposition, and collecting a compound from the formula 2) as is shown in the description; 2), putting the compound in a solvent to collect a compound in formula 3) as is shown in the description in a solvent reduced through a reducing agent; 3), putting the compound into the fluorobenzene to perform the Friedel-Crafts reaction to collect a compound in the formula 4) as is shown in the description; subjecting the compound and ethyl chloroformate to action to generate a compound in formula 5) as is shown in the description; 5), subjecting the compound and a compound shown in formula (XVII) to reaction prior to hydrolyzation to collect a compound in formula 6) as is shown in the description; 6), performing reduction with the reducing agent prior to hydrolyzing a reduction product and then collecting penfluridol (I). The penfluridol preparation method is high in yield, low in cost, moderate in reaction condition, short in circuit, proper for industrial production, low in three wastes, easy to treat and suitable for industrial production.
