- A study on the carboxylation of glycerol to glycerol carbonate with carbon dioxide: The role of the catalyst, solvent and reaction conditions
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Glycerol was reacted with CO2 (5 MPa) at 450 K in presence of Sn-catalysts (n-Bu2Sn(OMe)2 1, n-Bu2SnO 2 or Sn(OMe)2 3), using either glycerol or tetraethylene glycol dimethyl ether (tedmg) as reaction medium. 1 was much more active than 2. 1 was demonstrated to convert into n-Bu2Sn(glycerol-2H) 4 upon reaction with glycerol and elimination of MeOH. Monomeric 4 is proposed to be the active species in catalysis. It converted into a polymeric material with time with consequent reduction of its catalytic activity. Also, after the first catalytic cycle 4 was converted into an oligomeric material that did not contain glycerol. This also caused the reduction of the catalytic activity. 3 was able to uptake CO2 but was not able to promote the carboxylation of glycerol. 1 and 2 also promoted the trans-esterification of dimethylcarbonate (DMC) with glycerol to afford glycerol carbonate, but at a lower rate than the direct carboxylation of glycerol. This fact seems to rule out that the carboxylation of glycerol may proceed through the preliminary formation of DMC and its subsequent trans-esterification.
- Aresta, Michele,Dibenedetto, Angela,Nocito, Francesco,Pastore, Carlo
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- Reactions of dimethyl sulfite with diorganotin oxides. One-pot synthesis of methoxydiorganotin methanesulfonates through the arbuzov rearrangement, spectroscopic characterization of these compounds and their derivatives, and x-ray crystal structures of n-Bu2Sn(X)OS(O)2Me (X = acac, bzbz, OH)
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One-pot reactions of diorganotin oxides, R2SnO, with dimethyl sulfite under reflux conditions (125-127 °C) proceed via the Arbuzov rearrangement at the sulfur center, yielding the corresponding methoxydiorganotin methanesulfonates, R2Sn(OMe)OS(O)2Me [R = n-Pr (1), n-Bu (2), i-Bu (3), c-Hx (4)], as white, hygroscopic solids. These compounds react with β-diketones [acetylacetone (Hacac), benzoylacetone (Hbzac), and dibenzoylmethane (Hbzbz)] to afford mixed-ligand organotin derivatives, R2Sn(X)OS(O)2Me [X = acac, R = n-Pr (5), n-Bu (6); X = bzac, R = n-Pr (7), n-Bu (8); X = bzbz, R = n-Pr (9), n-Bu (10), i-Bu (11)]. Selective hydrolysis of the Sn-OMe bond in 1-3 occurs, resulting in the isolation of (μ-hydroxo)diorganotin methanesulfonates, R2Sn(OH)OS(O)2Me [R = n-Pr (12), n-Bu (13), i-Bu (14)]. All the compounds are characterized by elemental analyses and IR, multinuclear (1H, 13C, and 119Sn) NMR, and mass spectra. Unequivocal evidence of the presence of the methanesulfonate group is provided by the X-ray crystal structures of 6, 10, and 13. [For 6: trigonal space group R3? (No. 148), a = 28.664(1) A?, c = 13.056(1)A?, Z = 18. For 10: triclinic space group P1? (No. 2), a = 13.056(3) A?, b = 14.062(3) A?, c = 16.282(3) A?, Z = 4. For 13: triclinic space group P1? (No. 2), a = 9.089(2) A?, b = 12.040(2) A?, c =13.894(2) A?, Z = 2]. For 6 and 10, the solid-state structural analyses reveal dimeric structures with a bridging bidentate methanesulfonate group forming a centrosymmetric eight-membered ring. Compound 13 possesses a polymeric sheet structure with repeating 20-membered macrocycles (including two four-membered [Sn(OH)]2 rings) by virtue of the bridging bidentate methanesulfonate groups. A search for a possible pathway to give Arbuzov-rearranged products 1-4 leads us to speculate that there is an initial catalytic transformation of dimethyl sulfite to methyl methanesulfonate via intermediate compounds, Bu2Sn(OMe)2 (A) and [Bu2SnOMe]2O (B). A and B subsequently react with methyl methanesulfonate to give 1-4.
- Narula, Suraj P.
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- Etude DSC de la reaction de l'hydroperoxyde de t-butyle avec des derives thioorganostanniques
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La dcomposition de l'hydroperoxyde de t-butyle par les drivs thioorganostanniques a t tudie en faisant appel la DSC en programmation de temprature. Il a ainsi t montr que cette dgradation fait intervenir diverses ractions successives et que certains composs thioorganostanniques engendrent des espces capables de catalyser la dcomposition de l'hydroperoxyde de t-butyle.
- Bevilacqua,Pereyre,Maillard
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- ORGANOMETALLIC COMPOUNDS AND METHODS FOR THE DEPOSITION OF HIGH PURITY TIN OXIDE
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Disclosed herein are compounds useful for the deposition of high purity tin oxide. Also disclose are methods for the deposition of tin oxide films using such compounds. Such films demonstrate high conformality, high etch selectivity and are optically transparent. Such compounds are those of the Formula as follows R x -Sn-A 4-x wherein: A is selected from the group consisting of (Y a R' z ) and a 3- to 7-membered N- containing heterocyclic group; each R group is independently selected from the group consisting of an alkyl or aryl group having from 1 to 10 carbon atoms; each R' group is independently selected from the group consisting of an alkyl, acyl or aryl group having from 1 to 10 carbon atoms; x is an integer from 0 to 4; a is an integer from 0 to 1; Y is selected from the group consisting of N, O, S, and P; and z is 1 when Y is O, S or when Y is absent and z is 2 when Y is N or P.
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Paragraph 0104
(2019/02/17)
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- Process for Production of Alkyl Tin Alkoxide Compound, and Process for Production of Carbonic Acid Ester Using the Compound
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The present invention provides a process for producing: a compound represented by XOR2; a dialkyl tin dialkoxide compound having one tin atom, two Sn—R1 bonds and two Sn—OR2 bonds; and/or a tetraalkyl dialkoxy distannoxane compound having one Sn—O—Sn bond, in which each tin atom of the tetraalkyl dialkoxy distannoxane compound has two Sn—R1 bonds and one Sn—OR2 bond, the process comprising reacting in the absence of a catalyst at least one alkyl tin compound selected from the group consisting of i) and ii) below: i) a dialkyl tin compound having one tin atom, two Sn—R1 (wherein R1 represents an alkyl group) bonds, and two Sn—OX bonds (wherein OX is a group in which HOX that is a conjugate acid of OX is a Bronsted acid having a pKa of from 0 to 6.8); andii) a tetraalkyl distannoxane compound having one Sn—O—Sn bond, in which each tin atom of the tetraalkyl distannoxane compound has two Sn—R1 bonds and one Sn—OX bond (wherein OX is a group in which HOX that is a conjugate acid of OX is a Bronsted acid having a pKa of from 0 to 6.8); anda carbonic acid ester represented by R2OCOOR2 (wherein R2 represents a linear or branched, saturated or unsaturated hydrocarbon group, a hydrocarbon group having a saturated or unsaturated cyclic hydrocarbon substituent, or a Y—CH2— group (wherein Y represents an alkyl polyalkylene group, an aromatic group or a cyclic saturated or unsaturated alkylene ether group)), and/oran alcohol represented by R2OH (wherein R2 is the same as defined above).
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Page/Page column 49
(2010/12/18)
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- PROCESS FOR PRODUCTION OF ALKYL TIN ALKOXIDE COMPOUND, AND PROCESS FOR PRODUCTION OF CARBONATE ESTER USING THE COMPOUND
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The present invention provides a process for producing : a compound represented by XOR2; a dialkyl tin dialkoxide compound having one tin atom, two Sn-R1 bonds and two Sn-OR2 bonds; and/or a tetraalkyl dialkoxy distannoxane compound having one Sn-O-Sn bond, in which each tin atom of the tetraalkyl dialkoxy distannoxane compound has two Sn-R1 bonds and one Sn-OR2 bond, the process comprising reacting in the absence of a catalyst at least one alkyl tin compound selected from the group consisting of i) and ii) below: i) a dialkyl tin compound having one tin atom, two Sn-R1 (wherein R1 represents an alkyl group) bonds, and two Sn-OX bonds (wherein OX is a group in which HOX that is a conjugate acid of OX is a Bronsted acid having a pKa of from 0 to 6.8); and ii) a tetraalkyl distannoxane compound having one Sn-O-Sn bond, in which each tin atom of the tetraalkyl distannoxane compound has two Sn-R1 bonds and one Sn-OX bond (wherein OX is a group in which HOX that is a conjugate acid of OX is a Bronsted acid having a pKa of from 0 to 6.8); and a carbonic acid ester represented by R2OCOOR2 (wherein R2 represents a linear or branched, saturated or unsaturated hydrocarbon group, a hydrocarbon group having a saturated or unsaturated cyclic hydrocarbon substituent, or a Y-CH2- group (wherein Y represents an alkyl polyalkylene group, an aromatic group or a cyclic saturated or unsaturated alkylene ether group)), and/or an alcohol represented by R2OH (wherein R2 is the same as defined above).
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Page/Page column 66
(2010/09/17)
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- PROCESS FOR PRODUCING CARBONIC ESTER
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A method for producing a carbonic ester, comprising (1) performing a reaction between an organometal compound having a metal-oxygen-carbon linkage and carbon dioxide to obtain a reaction mixture containing a carbonic ester formed by the reaction, (2) separating the carbonic ester from the reaction mixture to obtain a residual liquid, and (3) reacting the residual liquid with an alcohol to form an organometal compound having a metal-oxygen-carbon linkage and form water and removing the water from the organometal compound, wherein the organometal compound obtained in step (3) is recovered for recycle thereof to step (1).
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