- New partially fluorinated epoxides by oxidation of olefins with sodium hypohalites under phase transfer catalysis
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Partially fluorinated epoxides can be readily prepared by oxidation of the corresponding olefins by NaOCl (or NaOBr) under phase transfer catalysis (PTC) conditions. Oxidation of CH2=C (CF3)2 at 0-5 °C leads to the formati
- Petrov, Viacheslav A.,Marshall, Will J.,Krespan, Carl G.,Cherstkov, Victor F.,Avetisian, Era A.
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- Reactions of 2,2-bis(trifluoromethyl)oxirane with alcohols under phase transfer catalysis
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It was demonstrated that the reaction of 2,2-bis(trifluoromethyl)oxirane (1) with variety of alcohols could be successfully carried out under phase transfer catalysis conditions using sodium or potassium hydroxide as a base. For example, reaction of CHsu
- Petrov, Viacheslav A.
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- Chiral fluorous dialkoxy-diamino zirconium complexes: Synthesis and use in stereospecific polymerization of 1-hexene
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New catalysts for the isospecific polymerization of 1-hexene based on cationic zirconium complexes incorporating the tetradentate fluorous dialkoxy-diamino ligands [OC(CF3)2CH2N(Me) (CH2)2N(Me)CH2C(CF3) 2O]2[(ON2NO)2-] and [OC(CF 3)2CH2N(Me)(1R,2R-C6,H 10)N(Me)CH2C(CF3)2O]2- [(ONCyNO)2-] have been developed. The chiral fluorous diamino-diol [(ONCyNO)H2, 2] was prepared by ring-opening of the fluorinated oxirane (CF3)2COCH2 with (R,R)-N,N′-dimethyl-1,2-cyclohexanediamine. Proligand 2 reacts cleanly with [Zr(CH2Ph)4] and [Ti(OiPr)4] precursors to give the corresponding dialkoxy complexes [Zr(CH2Ph) 2(ONCyNO)] (3) and [Ti(OiPr)2(ON CyNO)] (4), respec tively. An X-ray diffraction study revealed that 3 crystallizes as a 1:1 mixture of two diastereomers (Λ-3 and Δ3), both of which adopt a distorted octahedral structure with trans-O, cis-N, and cis-CH2Ph ligands. The two diastereomers Λ-3 and Δ-3 adopt a C2-symmetric structure in toluene solution, as established by NMR spectroscopy. Cationic complexes [Zr(CH2Ph)(ON 2NO)(THF)n]+ (n = 0, anion = [B(C 6F5)4]-, 5; n = 1, anion = [PhCH2B(C6F5)3]-, 6) and [Zr(CH2Ph)(ONCyNO)(THF)]+ [PhCH 2B(C6F5)3]- (7) were generatedfrom the neutral parent precursors [Zr(CH2Ph) 2(ON2NO)] (H) and [Zr(CH2Ph) 2(ONCyNO)] (3), and their possible structures were determined on the basis of 1H, 19F, and 13C NMR spectroscopy and DFT methods. The neutral zirconium complexes H and 3 (Λ3/Δ-3 mixture), when activated with B-(C6F 5)3 or [Ph3C] + [B(C 6F5)4]-, catalyze the polymerization of 1-hexene with overall activities of up to 4500 kg PH mol Zr lh-1, to yield isotactic-enriched (up to 74% mmmm) polymers with low-to-moderate molecular weights (Mw = 4800-47200) and monodisperse molecular-weight distributions (Mw/Mn = 1.17-1.79).
- Kirillov, Evgueni,Lavanant, Laurent,Thomas, Christophe,Roisnel, Thierry,Chi, Yun,Carpentier, Jean-Francois
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- Preparation and characterization of volatile alkaline-earth metal complexes with multiply coordinated aminoalkoxide ligands
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The aminoalkoxide complexes Sr(amak)2 (1) and Ba(amak)2 (2) were prepared by treatment of a multiply-chelating fluorinated aminoalcohol ligand HOC(CF3)2CH2N(CH2CH 2OMe)2, (amak)H, with the Group 2 metal reagents Sr(OPri)2 and BaH2 respectively. Single crystal X-ray diffraction studies indicate that complex 1 possesses an 8-coordinate distorted bicapped octahedral geometry with all O and N atoms coordinated to the central Sr cation. However, complex 2 adopts a unique 10-coordinate bicapped square antiprismatic structure, of which the coordination number is increased by two fluorine-to-barium dative interactions. Variable temperature 19F NMR studies show the existence of two inter-convertible isomers in solution and their possible molecular structures are proposed according to their structures in the solid-state. Preliminary investigation suggests that these complexes are good CVD source reagents for depositing SrF2 and BaF2 thin films.
- Chi,Ranjan,Chou,Liu,Peng,Lee
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- PREPARATION OF 2,2-BIS (FLUOROALKYL) OXIRANE AND PREPARATION OF PHOTOACID GENERATOR THEREFROM
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A 2,2-bis(fluoroalkyl)oxirane (A) is prepared by reacting a fluorinated alcohol (1) with a chlorinating, brominating or sulfonylating agent under basic conditions to form an oxirane precursor (2) and subjecting the oxirane precursor to ring closure under basic conditions. R1 and R2 are fluoroalkyl groups, R3 and R4 are hydrogen or monovalent hydrocarbon groups, X is chlorine, bromine or —OSO2R5 group, and R5 is alkyl or aryl.
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(2013/02/28)
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- PROCESS FOR PREPARING HEXAFLUOROISOBUTENE EPOXIDE
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Processes for preparing hexafluoroisobutene epoxide (HFIBO) from CH2=C(CF3)2 (HFIB) are provided. The processes can be carried out in substantial absence of oxidation catalysts.
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(2008/12/07)
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- POLYFLUORINATED EPOXIDES AND ASSOCIATED POLYMERS AND PROCESSES
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A method for producing partially fluorinated epoxides and corresponding polyether homopolymers of these polyfluorinated epoxides is described. Also described is a method for incorporating a fluoroalcohol functional group into a polymer as a pendant group. Certain perfluorinated olefins are also described. These polyfluorinated epoxides and the associated polymers and methods relating to them are useful components in photoresists, particulary in lithographic photoresists for use at low ultraviolet wavelengths (e.g., 157 nm).
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