629-14-1Relevant articles and documents
Selective synthesis of dimethoxyethane via directly catalytic etherification of crude ethylene glycol
Yu, Weiqiang,Lu, Fang,Huang, Qianqian,Lu, Rui,Chen, Shuai,Xu, Jie
supporting information, p. 3327 - 3333 (2017/07/28)
Etherification of ethylene glycol with methanol provides a sustainable route for the production of widely used dimethoxyethane; dimethoxyethane is a green solvent and reagent that is applied in batteries and used as a potential diesel fuel additive. SAPO-34 zeolite was found to be an efficient and highly selective catalyst for this etherification via a continuous flow experiment. It achieved up to 79.4% selectivity for dimethoxyethane with around 96.7% of conversion. The relationship of the catalyst's structure and the dimethoxyethane selectivity was established via control experiments. The results indicated that the pore structure of SAPO-34 effectively limited the formation of 1,4-dioxane from activated ethylene glycol, enhanced the reaction of the activated methanol with ethylene glycol in priority, and thus resulted in high selectivity for the desired products. The continuous flow technology used in the study could efficiently promote the complete etherification of EG with methanol to maintain high selectivity for dimethoxyethane.
Method for preparing alkyl diether compound
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Paragraph 0052-0054, (2017/08/30)
The invention relates to the field of synthesis of alkyl diether compounds, and provides a method for preparing an alkyl diether compound with the structure shown as the formula (I). The method comprises the steps that in the presence of concentrated sulfuric acid, an ethanediol compound with the structure shown as the formula (II) and olefin C1-C8 are subjected to a haptoreaction. The alkyl diether compound prepared through the preparation method is high in purity, low in impurity content and simple in preparation process, concentrated sulfuric acid is adopted as a catalyst to replace a traditional sodium alkoxide synthesis method, and high safety and high universality are achieved. The formulas are shown in the specification, wherein R1 and R2 independently serve as alkyl groups of C1-C8, and R1 and R2 do not serve as the alkyl groups at the same time, and R'1 is hydrogen or alkyl groups of C1-C8.
METHOD FOR PREPARING DOUBLE-SEALED-END GLYCOL ETHER
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Paragraph 0042; 0043; 0045; 0047, (2017/12/27)
Disclosed is a method for preparing a double end capped glycol ether, the method comprising: introducing into a reactor a raw material comprising a glycol monoether and a monohydric alcohol ether, and enabling the raw material to contact and react with an acidic molecular sieve catalyst to generate a double end capped glycol ether, a reaction temperature being 50-300° C., a reaction pressure being 0.1-15 MPa, a WHSV of the glycol monoether in the raw material being 0.01-15.0 h?1, and a mole ratio of the monohydric alcohol ether to the glycol monoether in the raw material being 1-100:1. The method of the present invention enables a long single-pass lifespan of the catalyst and repeated regeneration, has a high yield and selectivity of a target product, low energy consumption during separation of the product, a high economic value of a by-product, and is flexible in production scale and application.
Preparation method for double-terminated glycol ether
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Paragraph 0068; 0069; 0070; 0097, (2017/04/03)
The invention discloses a preparation method for double-terminated glycol ether. The preparation method comprises the following steps: a) introducing raw materials containing glycol monoether and monohydric ether alcohol into a reactor for contact and reaction with an acidic molecular sieve catalyst under the conditions that reaction temperature is 50 to 300 DEG C, reaction pressure is 0.1 to 15 MPa, the mass space velocity of the glycol monoether in the raw materials is 0.01 to 15.0/h, and a mol ratio of monohydric ether alcohol to glycol monoether in the raw materials is 1-100: 1, and separating obtained products so as to obtain a double-terminated glycol ether product, unreacted glycol monoether and monohydric ether alcohol, by-product components and other components; and b) returning the unreacted glycol monoether and monohydric ether alcohol and the by-product components obtained in the step a) to the reactor. The preparation method has the advantages that the catalyst has long single-pass life; the target product, i.e., double-terminated glycol ether has high yield and selectivity; energy consumption in separation of the products is low; by-products have high economic value; production scale can be large or small; and application of the method is flexible.
Preparation method for double-terminated glycol ether
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Paragraph 0049; 0050; 0051, (2017/07/25)
The invention relates to a preparation method for double-terminated glycol ether. The preparation method comprises a step of introducing raw materials containing glycol monoether and monohydric ether alcohol into a reactor for contact and reaction with an acidic molecular sieve catalyst so as to produce double-terminated glycol ether, wherein reaction temperature is 50 to 300 DEG C, reaction pressure is 0.1 to 15 MPa, the mass space velocity of the glycol monoether in the raw materials is 0.01 to 15.0/h, and a mol ratio of monohydric ether alcohol to glycol monoether in the raw materials is 1-100: 1. The preparation method has the advantages that the catalyst has long single-pass life and can be repeatedly regenerated; the target product, i.e., double-terminated glycol ether has high yield and selectivity; energy consumption in separation of products is low; by-products have high economic value; production scale can be large or small; and application of the method is flexible.
A method of manufacturing an alkylene glycol ether (poly)
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Paragraph 0046; 0047, (2016/10/17)
PROBLEM TO BE SOLVED: To provide a method for producing a (poly)alkylene glycol diether, introducing the oxyalkylene groups of the optional mole number of addition and optional terminal alkyl groups by using a metallosilicate catalyst having 10 to 1,000 ratio of SiO2/M2O3as an ether interchange reaction catalyst. SOLUTION: This method for producing the (poly)alkylene glycol diether includes a process of obtaining the (poly)alkylene glycol diether by the ether interchange reaction of a first (poly)alkylene glycol monoether with a second (poly)alkylene glycol monoether in the presence of the metallosilicate catalyst having 10 to 1,000 ratio of SiO2/M2O3(wherein, M is ≥1 kind selected from the group consisting of Al, Ga, Ge, B, Zn, P, Zr, Ti, Cr, Be, V and As). COPYRIGHT: (C)2012,JPOandINPIT
The pentamethylcyclopentadienylsilicon(II) cation as a catalyst for the specific degradation of oligo(ethyleneglycol) diethers
Leszczynska, Kinga,Mix, Andreas,Berger, Raphael J. F.,Rummel, Britta,Neumann, Beate,Stammler, Hans-Georg,Jutzi, Peter
supporting information; experimental part, p. 6843 - 6846 (2011/09/19)
Catalytic open sandwiches: Oligo(ethyleneglycol) diethers RO(CH 2CH2O)nR are degraded by the unusual catalyst Cp Si+ (see scheme). The open coordination sphere at silicon allows up to four Si-O contacts; crystal structure data of the reactive compounds [Cp Si(dme)]+BR4- and [Cp Si([12]crown-4)] +BR4- (R=C6F5) show weakly bound ether molecules. Copyright
Vinylic Substitution of 1,2-Dibromo-1,2-difluoroethylene and Tribromofluoroethylene. An Intramolecular kBr/kF Element Effect and Apparent Inversion of Configuration in SNV Reactions
Shainyan, Bagrat A.,Rappoport, Zvi
, p. 3421 - 3428 (2007/10/02)
The reactions of (E/Z)-1,2-dibromo-1,2-difluoroethylene(1) and of tribromofluoroethylene (2) with alkoxide ions and of 1 with p-toluenethiolate ion give multiplicity of products.The reaction of 1 with 1 equiv of NaOMe gives mainly a 2:1 mixture of the product of one bromine displacement, together with methyl dimethoxyacetate (3), methyl bromofluoroacetate (4), 1,1,2-trifluoro-2-bromoethyl ether (7), and 1,1-difluoro-1,2,2-trimethoxyethane (8).With 2 equiv of MeO(1-) 3 and 4 are the main products, and at 130 deg C, dimethyl ether 5 is also formed.With EtOCH2CH2O(1-) 1 gave 2-ethoxyethyl bromofluoroacetate (9), bis(2-ethoxyethyl) ether (10), and E/Z mixtures of the substitution products EtOCH2CH2OC(F)=C(F)Br (12) and EtOCH2CH2OC(Br)=C(F)Br (13).Reaction of 2 with excess RO(1-) (R = Me, Et) gives alkyl dibromoacetates, while with 1 equiv of RO(1-) only a bromine from the =C(F)Br carbon is displaced.Reaction of 1 with p-TolSNa in MeOH gives the reduction-substitution product p-TolSC(F)=CHF (18), together with (P-TolS)2 (16) and p-TolSMe (17).The same reaction in DMSO gives E/Z mixtures of the product of displacement of one bromine (19) or two bromines (20).Formation of the products is rationalized by an initial nucleophilic attack on the vinylic carbon followed by leaving group expulsion, giving, e.g., 12, 13, 19, or 20.Hydrolysis of the intermediate or addition of HF to the initial substition product gives saturated products, e.g., 3, 4, 7, or 8, while SN2 reactions on the ether oxygen give ethers 5 and 10.A bromophilic reaction gives the reduction-substitution product 18, while hydrolysis-decarboxylation leads to 17.The regiospecificity of the nucleophilic addition is due to polar and hyperconjugative effects.An intramolecular element effect kBr/kF of > 10 is reported for the first time in the reaction of 1 with EtOCH2CH2O(1-).This value and the absence of such effects in other reactions are consistent with a much higher nucleofugality from a (1-)CC(F)Br system of Br(1-) compared with F(1-).The E/Z compositions of 18-20 indicates an apparent inversion in their formation, but it is not known whether these compositions are thermodynamically or kinetically controlled.
Deamination Reactions, 41. Reactions of Aliphatic Diazonium Ions and Carbocations with Ethers
Kirmse, Wolfgang,Jansen, Ulrich
, p. 2607 - 2625 (2007/10/02)
Aliphatic diazonium ions and carbocations were generated by deacylation of appropriate nitrosoureas (1, 5, 9) in alcohol-ether mixtures or in 2-alkoxyethanols.Ethers were generally inferior to alcohols in capturing cationic intermediates.Formation of trialkyloxonium ions led to alkyl exchange or ring opening.The observed reactivity orders were n-butyl > isobutyl for the diazonium ions, allyl > sec-butyl > tert-butyl for the carbocations, methoxy > ethoxy and oxirane > oxetane > tetrahydrofuran for the ethers, indicating the predominance of steric effects.Neighboring group participation in 4-methoxy-1-butanediazonium ions (58) and 4,5-epoxy-1-pentanediazonium ions (74) was detectable but inefficient ( 20percent of cyclic oxonium ions).
