16519-02-1Relevant articles and documents
A Unified and Desymmetric Approach to Chiral Tertiary Alkyl Halides
Huang, Zhongxing,Low, Kam-Hung,Zhang, Suihan,Zheng, Yin,Zi, Weiwei
supporting information, p. 1951 - 1961 (2022/02/09)
Enantioenriched tertiary alkyl halides are prevalent in bioactive molecules and can serve as versatile synthetic intermediates to construct complex structures. While conventional access to these motifs often hinges on stereoselective carbon-halogen or carbon-carbon bond formation reactions, desymmetric approaches using halogenated and prochiral tetrasubstituted carbons are largely elusive in comparison. Here, we report that a suite of dinuclear zinc catalysts with a prolinol- or pipecolinol-derived tetradentate ligand can reductively desymmetrize a large collection of easily available halomalonic esters to α-halo-β-hydroxyesters. These polyfunctionalized tertiary alkyl fluorides, chlorides, and bromides proved to be useful intermediates toward fluorinated drug analogs and polyhalogenated monoterpenes. The facile intramolecular epoxidation of the chiral chloride and bromide products has also enabled expeditious access to natural products containing tertiary alcohol motifs.
New promising lithium malonatoborate salts for high voltage lithium ion batteries
Sun, Xiao-Guang,Wan, Shun,Guang, Hong Yu,Fang, Youxing,Reeves, Kimberly Shawn,Chi, Miaofang,Dai, Sheng
, p. 1233 - 1241 (2017/02/05)
Three new lithium salts, lithium difluoro-2-methyl-2-fluoromalonatoborate (LiDFMFMB), lithium difluoro-2-ethyl-2-fluoromalonatoborate (LiDFEFMB), and lithium difluoro-2-propyl-2-fluoromalonatoborate (LiDFPFMB), have been synthesized and evaluated for application in lithium ion batteries. These new salts are soluble in a mixture of ethylene carbonate (EC) and ethyl methyl carbonate (EMC) (1:2 by wt) and 1.0 M salt solutions can be easily prepared. The ionic conductivities of these new salts are close to those of LiBF4 and LiPF6. Cyclic voltammograms reveal that these new salt based electrolytes can passivate both natural graphite and high voltage spinel LiNi0.5Mn1.5O4 (LNMO) to form effective solid electrolyte interphases (SEIs). In addition, these new salt-based electrolytes exhibit good cycling stability with high coulombic efficiencies in both LiNi0.5Mn1.5O4 and graphite based half-cells and full cells.
METHOD FOR PRODUCING FLUOROMALONIC ESTER DERIVATIVE
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Paragraph 0031-0033, (2017/02/24)
PROBLEM TO BE SOLVED: To provide a method for producing a fluoromalonic ester derivative, useful as a raw material of electronic materials and as a synthetic intermediate of an agrochemical, which does not use or waste an expensive fluorinating agent and also has a short process. SOLUTION: A fluoromalonic ester derivative represented by a formula (2) is produced by reacting a malonic ester derivative with the 2-position modified with R3 with N-fluoro-bis(methanesulfonyl)imide in the presence of a Lewis acid. (R1 and R2 are each independently a methyl group, an ethyl group, a C3-4 linear, branched or cyclic alkyl group, a phenyl group, or a benzyl group; and R3 is H, a methyl group or an ethyl group.) SELECTED DRAWING: None COPYRIGHT: (C)2016,JPO&INPIT
