2050-23-9Relevant articles and documents
Reductive Alkylation of Alkenyl Acetates with Alkyl Bromides by Nickel Catalysis
Bai, Yunfei,Han, Guan-Yu,He, Rong-De,Liu, Xue-Yuan,Pan, Xiaobo,Pang, Xiaobo,Shu, Xing-Zhong,Zhao, Zhen-Zhen
supporting information, (2021/12/14)
Catalytic alkylation of stable alkenyl C?O electrophiles is synthetically appealing, but studies to date have typically focused on the reactions with alkyl Grignard reagents. We report herein a cross-electrophile reaction of alkenyl acetates with alkyl bromides. This work has enabled a new method for the synthesis of aliphatic alkenes from alkenyl acetates to be established that can be used to add more structural complexity and molecular diversity with enhanced functionality tolerance. The method allows for a gram-scale reaction and modification of biologically active molecules, and it affords access to useful building blocks. Preliminary mechanistic studies reveal that the NiI species plays an essential role for the success of the coupling of these two reactivity-mismatched electrophiles.
Microwave-Assisted Nickel-Catalyzed Rapid Reductive Coupling of Ethyl 3-iodopropionate to Adipic Acid
Zhang, Linfeng,Zheng, Jing,Zou, Wenya,Shu, Yongqi,Yang, Weiran
, p. 2339 - 2345 (2021/01/04)
Abstract: 3-iodopropionic acid (3-IPA) can be efficiently synthesized from the glycerol derivative glyceric acid (GA), which is a potential biomaterial-based platform molecule. In this report, ethyl 3-iodopropionate was rapidly dimerized to diethyl adipate in a microwave reactor using NiCl2·6H2O as a catalyst, co-catalyzed by Mn and the 1, 10-Phenanthroline monohydrate ligand. Under the optimum reaction conditions, diethyl adipate can be obtained with 84% yield at 90?°C in just 5?min. Diethyl adipate was hydrolyzed to obtain the adipic acid (AA) in 89% yield with an acid catalyst. AA is an important chemical and a monomer for producing a wide range of high-performance polymeric substances. This rapid coupling method is also applicable to other alkyl halides. Graphic Abstract: [Figure not available: see fulltext.]
Ni-Catalyzed β-Alkylation of Cyclopropanol-Derived Homoenolates
Mills, L. Reginald,Zhou, Cuihan,Fung, Emily,Rousseaux, Sophie A. L.
supporting information, p. 8805 - 8809 (2019/11/03)
Metal homoenolates are valuable synthetic intermediates which provide access to β-functionalized ketones. In this report, we disclose a Ni-catalyzed β-alkylation reaction of cyclopropanol-derived homoenolates using redox-active N-hydroxyphthalimide (NHPI) esters as the alkylating reagents. The reaction is compatible with 1°, 2°, and 3° NHPI esters. Mechanistic studies imply radical activation of the NHPI ester and 2e β-carbon elimination occurring on the cyclopropanol.
Photoredox/Nickel Dual Catalysis for the C(sp3)–C(sp3) Cross-Coupling of Alkylsilicates with Alkyl Halides
Lévêque, Christophe,Corcé, Vincent,Chenneberg, Ludwig,Ollivier, Cyril,Fensterbank, Louis
supporting information, p. 2118 - 2121 (2017/04/24)
Alkylsilicates were engaged under photoredox/nickel dual catalysis conditions with alkyl halides for the first time. The C(sp3)–C(sp3) cross-coupling products were obtained in moderate yields and were accompanied by the homocoupling
The synthesis of di-carboxylate esters using continuous flow vortex fluidics
Britton, Joshua,Dalziel, Stuart B.,Raston, Colin L.
, p. 2193 - 2200 (2016/04/19)
A vortex fluidic device (VFD) is effective in mediating the synthesis of di-esters at room temperature. Processing under ambient conditions allows for a simple and efficient synthesis, whilst operating under continuous flow addresses scalability. The rotational speed of the sample tube and the flow rate were critical variables during reaction optimization, and this relates to the behaviour of the fluid flow at a molecular level. Whilst at specific rotational speeds the tube imparts a vibrational response into the fluid flow, the flow rate dictates residence time and the ability to maintain high levels of shear stress. The combination of mechanically induced vibrations, rapid micromixing, high levels of shear stress and water evaporation results in yields up to 90% for 3.25 minutes or less residence time. These results are key for devising greener and more efficient processes both mediated by the VFD and other continuous flow platforms.
Cobalt-Catalyzed Csp3?Csp3Homocoupling
Cai, Yingxiao,Qian, Xin,Gosmini, Corinne
supporting information, p. 2427 - 2430 (2016/08/16)
An efficient and easy method for Csp3?Csp3homocoupling was developed using cobalt bromide as catalyst. A series of functionalized alkyl bromides and alkyl chlorides were coupled in high yields under mild conditions. This reaction seems to involve a radical intermediate. (Figure presented.).
Lewis Base Activation of Silyl Acetals: Iridium-Catalyzed Reductive Horner-Wadsworth-Emmons Olefination
Dakarapu, Udaya Sree,Bokka, Apparao,Asgari, Parham,Trog, Gabriela,Hua, Yuanda,Nguyen, Hiep H.,Rahman, Nawal,Jeon, Junha
supporting information, p. 5792 - 5795 (2015/12/11)
A Lewis base promoted deprotonative pronucleophile addition to silyl acetals has been developed and applied to the iridium-catalyzed reductive Horner-Wadsworth-Emmons (HWE) olefination of esters and the chemoselective reduction of the resulting enoates. Lewis base activation of silyl acetals generates putative pentacoordinate silicate acetals, which fragment into aldehydes, silanes, and alkoxides in situ. Subsequent deprotonative metalation of phosphonate esters followed by HWE with aldehydes furnishes enoates. This operationally convenient, mechanistically unique protocol converts the traditionally challenging aryl, alkenyl, and alkynyl esters to homologated enoates at room temperature within a single vessel.
Nickel-catalyzed cross-electrophile coupling of 2-chloropyridines with alkyl bromides
Everson, Daniel A.,Buonomo, Joseph A.,Weix, Daniel J.
supporting information, p. 233 - 238 (2014/02/14)
The synthesis of 2-alkylated pyridines by the nickel-catalyzed cross-coupling of two electrophiles, a 2-chloropyridine and an alkyl bromide, is described. Compared with our previously published conditions for aryl halides, this method uses a different, more rigid, bathophenanthroline ligand and is conducted at high concentration in N,N-dimethylformamide as solvent. The method displays promising functional group compatibility and the conditions are orthogonal to those for the Stille coupling.Georg Thieme Verlag Stuttgart.
PYRIDIN-2YL SULFANYL ACID ESTERS AND PROCESS FOR THE PREPARATION THEREOF
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Paragraph 0090; 0115-0126, (2013/06/04)
The present invention relates to Pyridin-2-yl sulfanyl acid ester compounds having antiinflammatory properties. The present invention particularly relates to novel anti-inflammatory heterocyclic acid esters of Pyridin-2-yl sulfanyl having the structure of general formula 1 which have been screened for their antiinflammatory activity with respect to inhibition of adhesion of neutrophils, isolated from human peripheral blood, onto the surface of human umbilical vein endothelial cells (HU-VEC) as a result of inhibition of the cytokine-stimulated expression of cell adhesion molecule ICAM-1. The compound RS—Z, 3-(Pyridin-2-yl sulfanyl)-propionic acid pentyl ester (structure 1a, R1=H, R2=H, R3=CH2-COOC5H11) was found to be most effective for ICAM-1 and neutrophil adhesion inhibition and was found to effectively alleviate inflammation mediated by excessive leukocyte infiltration leading to inflammatory disorders or like conditions, such as acute lung injury and acute respiratory distress syndrome in mice.
Electrocatalytic debromination of open-chain and cyclic dibromides in ionic liquids with cobalt(II)salen complex as mediator
Shen, Yi,Inagi, Shinsuke,Atobe, Mahito,Fuchigami, Toshio
, p. 89 - 99 (2013/02/25)
The electrocatalytic reduction of open-chain and cyclic dibromides in ionic liquids, mediated by cobalt(II)salen, was investigated. Macro-scale constant-potential electrolysis in an undivided cell gave the corresponding debrominated products in moderate to good yields. The workup process after electrolysis proved to be much simpler in the ionic liquid than that in organic solvents. The possibility of reuse of the ionic liquid was demonstrated.