- Mechanistic Analysis and Characterization of Intermediates in the Phosphane-Catalyzed Oligomerization of Isocyanates
-
The mechanism of the oligomerization of aliphatic isocyanates catalyzed by trialkylphosphanes has been studied through low temperature 31P and 15N NMR spectroscopy combined with computational chemistry. A revised mechanism is proposed that contains several (spiro)cyclic pentacoordinate phosphorous intermediates. Previously reported spectroscopic data of a transient intermediate has been reevaluated and assigned to a cyclic intermediate containing a P?N bond by experiments with 15N-labeled isocyanate. 13C, 15N, and 31P NMR shifts that support this assignment have been calculated using quantum chemical methods.
- Helberg, Julian,Oe, Yohei,Zipse, Hendrik
-
-
Read Online
- Production of cyclic carbonate
-
The purpose of the present invention is to provide a practical method for producing a cyclic carbonate, which is widely used for various applications such as electrolytic solutions for lithium-ion secondary batteries and plastic materials, by a reaction between an epoxide (oxirane) and carbon dioxide, the method giving consideration to the reduction of environmental loads and making it possible to produce said cyclic carbonate with high yield under mild conditions, such as at room temperature and atmospheric pressure. The present invention relates to a method for producing a cyclic carbonate, the method being characterized by reacting an epoxide and carbon dioxide in the presence of an iodine-anion-containing phosphonium salt and a compound including a hydrogen atom that can form a hydrogen bond with an oxygen atom in the epoxide.
- -
-
Paragraph 0128
(2017/11/08)
-
- METHOD FOR PRODUCING IONIC LIQUID AND METHOD FOR PRODUCING INTERMEDIATE BODY FOR PRODUCTION OF IONIC LIQUID
-
PROBLEM TO BE SOLVED: To provide a method for producing an ionic liquid for synthesizing a desired ionic liquid with high purity, and to provide a method for producing an intermediate body for synthesizing the ionic liquid. SOLUTION: A method for producing an ionic liquid which produces a desired ionic liquid Q+Z- formed from cation Q+ and anion Z- includes: a step of purifying a high-melting point intermediate body Q+Y- that is formed from the cation Q+ and the anion Z- and has such a melting point as to be recrystallized, by recrystallization; and a step of obtaining the ionic liquid Q+Z- directly or indirectly from the purified high-melting point intermediate body Q+Y-. A method for producing a strongly acidic intermediate body and a super-hydrophilic intermediate body includes: a step of obtaining a strongly acidic intermediate body or a super-hydrophilic intermediate body from the purified high-melting point intermediate body Q+Y- by a double decomposition precipitation method or obtaining the strongly acidic intermediate body from the purified high-melting point intermediate body Q+Y- by a double decomposition precipitation method, or a step of obtaining the super-hydrophilic intermediate body from the strongly acidic intermediate body by a neutralization method. SELECTED DRAWING: Figure 1 COPYRIGHT: (C)2018,JPOandINPIT
- -
-
Paragraph 0112
(2018/02/22)
-
- Effective synthesis of cyclic carbonates from carbon dioxide and epoxides by phosphonium iodides as catalysts in alcoholic solvents
-
Phosphonium iodides effectively catalyzed the reaction of CO2 and epoxides under mild conditions such as ordinary pressure and ambient temperature in 2-propanol, and the corresponding five-membered cyclic carbonates were obtained in high yields.
- Aoyagi, Naoto,Furusho, Yoshio,Endo, Takeshi
-
supporting information
p. 7031 - 7034
(2013/12/04)
-
- Basic hydrolysis of 1,4-bis(triphenylphosphonio)buta-1,3-diene dihalides
-
Basic hydrolysis of 1,4-bis(triphenylphosphonio)buta-1,3-diene dichloride with 10% NaOH gave isomeric 4-diphenylphosphoryl-4-phenylbut-1(2)-enes and 1-diphenylphosphoryl-1-phenylbuta-1,3-diene, the products of anionotropic migration of a phenyl group from the P atom to the -position. Hydrolysis with Na2CO3 afforded only the diene product. In both cases, triphenylphosphine and triphenylphosphine oxide were isolated as secondary products. Dehydrochlorination of 2-chloro-1,4-bis(triphenylphosphonio) but-2-ene dibromide with triphenylphosphine was proposed as a new convenient route to 1,4-bis(triphenylphosphonio)buta-1,3-diene dibromide.
- Ovakimyan,Pogosyan,Movsisyan,Indzhikyan
-
experimental part
p. 560 - 564
(2011/02/17)
-
- -
-
Thiomethyl nickel complexes [Ni(CH2SR)2(PBu3)2] (R = Me (1a), tBu (1b), Ph (1c)) and the homoleptic derivatives [{Li(Et2O)}2Ni(CH2StBu)4] (2), [Li2Ni(CH2SMe)4] · x thf (3a) and [Li2Ni(CH2SPh)4] · x Et2O (3b) were synthesized by the reaction of nickel halide phosphine complexes with the appropriate thiomethyl lithium compounds LiCH2SR in a molar ratio of 1/2 and 1/4, respectively. The molecular structures (X-ray) of the diamagnetic heteroleptic derivatives 1 exhibit Ci symmetry with square-planar NiC2P2 units. The ligands are arranged in trans-position. The complexes 1 were characterized by microanalysis and by NMR spectroscopy. The terf-butylthiomethyl complex 2 is stable at room temperature (Tdec. ~ 60-66°C) whereas the methyl- and phenylthiomethyl complexes 3a and 3b are decomposed already at - 10 to - 20°C. The molecular structure (X-ray) of complex 2 shows a slightly distorted planar arrangement of the four methylene carbon atoms and nickel (d(Ni-C) = 1.944(3)-2.004(3) A). The lithium atoms are distorted tetrahedrally coordinated by two sulfur atoms, one oxygen atom (Et2O) and one methylene carbon atom. The short Li-S distances (2.461(6)-2.535(5) A) indicate strong lithium-sulfur interactions.
- Becke, Frank,Rueffer, Tobias,Boese, Roland,Blaeser, Dieter,Steinborn, Dirk
-
p. 169 - 178
(2007/10/03)
-
- 1H-NMR- AND MOESSBAUER INVESTIGATIONS ON THE ION PAIRS OF TETRACHLOROFERRATE(III) ANION WITH QUATERNARY PHOSPHONIUM CATIONS
-
Paramagnetic ion pairs were investigated by 1H-NMR and Moessbauer spectroscopy in chloroform and dimethyl sulphoxide.It has been shown that the chemical shifts of 1H-NMR peaks arise from a combination of contact and pseudocontact interactions of opposite sign, and the ratio of interactions was definitely influenced by the extent of solvation.On the basis of Moessbauer measurements it was shown that the change of the cation size had an effect on the electron delocalization and symmetry conditions of iron(III) in solid samples, too.In concentrated frozen solutions of ion pairs, different interactions were indicated by Moessbauer spectros copy in chloroform and dimethyl sulphoxide, in accordance with 1H-NMR results.However, in dilute solution such an anion-solvent interaction was observed directly, which could be shown by the NMR method only indirectly.
- Vincze, L.,Papp, S.
-
p. 153 - 162
(2007/10/02)
-