- Bifunctional Fluoroalcohol Catalysts Enabled Sustainable Synthesis of Poly(amino acid)s?
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A series of novel bifunctional single-molecule hydrogen-bonding organocatalysts based on fluorinated tertiary alcohol were synthesized to mediate the metal-free polymerization of α-amino acid N-carboxyanhydride (NCA) monomer. Through the screening of catalysts, the polymerization catalyzed by the preferred bifunctional fluoroalcohol catalyst proceeded in a fast and controlled manner, affording high molecular weight polypeptide up to 35.2 × 104 Da with relatively narrow molecular weight distribution (? 1.20). A phenomenon of self-accelerating effect of polymerization induced by α-helical structure of polypeptides was observed, and a possible polymerization pathway has been discussed.
- He, Wenjing,Tao, Youhua
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supporting information
p. 2119 - 2124
(2021/06/16)
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- A dendritic macromolecule fluorine - 19 magnetic resonance developer and its preparation method and application (by machine translation)
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The invention discloses a dendritic macromolecule fluorine - 19 magnetic resonance developer and its preparation method and application. Developer of the present invention is to fluorine-containing dendritic macromolecule as the skeleton, peripheral end group is connected with the functional molecule, its preparation method comprises the following steps: through the Lewis acid under the catalysis of the Friedel-crafts reaction of hexafluoroacetone with benzene will double-trifluoromethyl tertiary alcohol introduction benzene, in fuming sulfuric acid under the action of the iodination reaction, and then introduced into the propynyl structure through the coupling reaction, hydrogenating the resultant fluorine-containing structure unit Q; phosphorus tribromide in Q through the primary conversion of hydroxy group to bromine, then in hydroxy Q with the bromo generating ether linkage synthesis of 1st on behalf of the dendritic macromolecule, repeated brominated and ether generating reaction to obtain 2nd, three generations of dendritic macromolecule, finally through the brominated 3rd on behalf of the branched chain with the ligand through ether bond and to obtain the developer of the present invention. Developer of the present invention can be used for magnetic resonance imaging and the quantitative, visual, transmission and release and the like field. (by machine translation)
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- Syntheses and lipophilicities of tetraarylborate ions substituted with many trifluoromethyl groups
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Syntheses were investigated using various tetraarylborate ions with a large number of trifluoromethyl groups: tetrakisborate; tetrakisborate; tetrakisborate; and tetrakisborate ions.The preparation of Grignard reagents and the subsequent reaction with boron trifluoride etherate are importantsteps for a higher yield and easier isolation of the product.Sodium- and tetramethylammonium salts of these borate ions are soluble in halocarbon solvents such as dichloromethane, chloroform and 1,2-dibromotetrafluoroethane.
- Fujiki, Kanji,Kashiwagi, Mitsuyoshi,Miyamoto, Hideyuki,Sonoda, Akinari,Ichikawa, Junji,et al.
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p. 307 - 321
(2007/10/02)
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- PREPARATION OF 1,3,5-TRIS(2-HYDROXYHEXAFLUORO-2-PROPYL)BENZENE AND SOME OF ITS DERIVATIVES
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Grignard and lithium exchange methods have been used to prepare the polyfluoro alcohol, 1,3,5-tris(2-hydroxyhexafluoro-2-propyl)benzene.Preparation of the tris glycidyl ether of this alcohol and other derivatives are reported.
- Soulen, Robert L.,Griffith, James R.
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p. 203 - 210
(2007/10/02)
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- PERFLUOROALKYLATION OF BENZENE DERIVATIVES. AN IMPROVED SYNTHESIS OF 1,3-BIS(2-HYDROXYHEXAFLUORO-2-PROPYL)-5-(PERFLUORO-n-ALKYL)BENZENES
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A three-step high yield synthesis of various 1,3-bis(2-hydroxyhexafluoro-2-propyl)-5-perfluoro-n-alkyl) benzenes is described.Significant improvements in the iodination and perfluoro-alkylation of a perfluoroalkylbenzene diol have been achieved.Copper coupling of straight-chain perfluoroalkyl iodides with the iodobenzene derivative in DMSO gave the desired compounds as DMSO complexes in 78-91 percent yield.
- Sepiol, Janiusz,Soulen, Robert L.
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