592-20-1Relevant articles and documents
Investigation of homopolymerization rate of perfluoro-4,5-substituted-2- methylene-1,3-dioxolane derivatives and properties of the polymers
Yang, Yu,Mike?, Franti?ek,Yang, Liang,Liu, Weihong,Koike, Yasuhiro,Okamoto, Yoshiyuki
, p. 277 - 281 (2006)
Five perfluoro-4,5-substituted-2-methylene-1,3-dioxolane monomers were synthesized. These monomers were found to readily polymerized by a free radical initiator in bulk and/or in solutions. Homopolymerization rates were determined using in situ 19F NMR measurements and found to be 0.25 to 1.66 × 10-4 mol L-1 s-1 in 1,1,2-trichlorotrifluoroethane at 41°C using the perfluorodibenzoyl peroxide as an initiator. The rates depend on the substituents on the 4 and 5 positions of the dioxolane. The purified polymers were thermally stable (up to 350°C). They show low refractive indexes (1.33-1.36 at 532 nm). They are transparent from UV to near IR region and have high glass transition temperatures (100-170°C).
AMBER ODORANT
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Page/Page column 29, (2020/12/11)
The present invention concerns compound of formula (I) in the form of any one of its stereoisomers or as a mixture thereof, and wherein R1 represents a hydrogen atom, a C1-3 alkyl group or C2-3 alkenyl group; X represents an oxygen atom when R2 represents a C1-4 alkyl group or C2-4 alkenyl group or X represents a CH2-O group when R2 represents a C2-4 alkenyl group or a MeC=O group. The use as a perfuming ingredient of the invention's compound and the invention's compound as part of a perfuming composition or of a perfuming consumer product are also part of the present invention.
Exploring the catalytic activity of Lewis-acidic uranyl complexes in the nucleophilic acyl substitution of acid anhydrides
Takao, Koichiro,Akashi, Shin
, p. 12201 - 12207 (2017/03/08)
The catalytic activities of several uranyl complexes, such as N,N′-disalicylidene-o-phenelyenediaminato(ethanol)dioxouranium(vi) (UO2(salophen)EtOH), bis(dibenzoylmethanato)(ethanol)dioxouranium(vi) (UO2(dbm)2EtOH), pentakis(N,N-dimethylformamide)dioxouranium(vi) ([UO2(DMF)5]2+), and tetrakis(triphenylphosphine oxide)dioxouranium(vi) ([UO2(OPPh3)4]2+), were examined in the nucleophilic acyl substitution of acid anhydrides. Among them, [UO2(OPPh3)4]2+ was the most efficient to give ethyl acetate and acetic acid from acetic anhydride (Ac2O) and ethanol, and was resistant towards decomposition during the catalytic reaction. Several nucleophiles were also subjected to the catalytic acylation reaction using acetic and pivalic anhydride. Kinetic and spectroscopic studies suggested that [UO2(OPPh3)4]2+ interacts with Ac2O to form [UO2(Ac2O)(OPPh3)3]2+. Interaction of this actual catalyst with additional Ac2O determines the rate of the overall nucleophilic acyl substitution reaction.
N-Isocyanimino-Triphenylphosphorane (Ph 3Pnnc) as an Efficient Reagent for the Preparation of Fully Substituted 1,3,4-Oxadiazoles via Intramolecular Aza-Wittig Reaction in Water
Jafari, Ali,Ramazani, Ali,Asiabi, Pegah Azimzadeh,Sadri, Fariba,Joo, Sang Woo
, p. 2246 - 2254 (2015/12/20)
An efficient green protocol for the synthesis of 1,3,4-oxadiazoles derivatives via a one-pot three-component reaction of aromatic carboxylic acids, N-isocyanimino-Triphenylphosphorane and ester derivatives of 2-oxopropyl alcohol (2-oxopropyl benzoate, 2-oxopropyl-4-bromobenzoate and 2-oxopropyl acetate) in water at room temperature have been developed. The present methodology offers several advantages such as a simple procedure, high yields, environmental friendliness and the absence of any volatile and hazardous organic solvents.