- Synthesis of propylene glycol ethers from propylene oxide catalyzed by environmentally friendly ionic liquids
-
A series of acetate ionic liquids were synthesized using a typical two-step method. The ionic liquids were used as environmentally benign catalysts in the production of propylene glycol ethers from propylene oxide and alcohols under mild conditions. The basic strengths of the ionic liquids were evaluated by determination of their Hammett functions, obtained using ultraviolet-visible spectroscopy, and the relationship between their catalytic activities and basicities was established. The catalytic efficiencies of the ionic liquids were higher than that of the traditional basic catalyst NaOH. This can be attributed to the involvement of a novel reaction mechanism when these ionic liquids are used. A possible electrophilic-nucleophilic dual activation mechanism was proposed and confirmed using electrospray ionization quadrupole time-of-flight mass spectrometry. In addition, the effects of significant reaction parameters such as concentration of catalyst, molar ratio of alcohol to propylene oxide, reaction temperature, and steric hindrance of the alcohol were investigated in detail.
- Zhao, Cong,Chen, Shengxin,Zhang, Ruirui,Li, Zihang,Liu, Ruixia,Ren, Baozeng,Zhang, Suojiang
-
p. 879 - 888
(2017/05/24)
-
- Epoxide hydrolysis and alcoholysis reactions over crystalline Mo-V-O oxide
-
Crystalline Mo-V-O oxides have been used as a catalyst for the hydrolysis and alcoholysis of propylene oxide to diols and ethers, respectively. Relationships between the active crystal facet, the acidity of Mo-V-O catalysts and the activity have been established. Our results indicate that the a-b plane is the active facet for the hydrolysis reaction.
- Zhang, Xiaochen,Wang, Min,Zhang, Chaofeng,Lu, Jianmin,Wang, Yehong,Wang, Feng
-
p. 70842 - 70847
(2016/08/05)
-
- Catalytic etherification of glycerol with short chain alkyl alcohols in the presence of Lewis acids
-
Here we report the homogeneously-catalyzed etherification of glycerol with short chain alkyl alcohols. Among the large variety of Bronsted and Lewis acids tested, we show here that metal triflates are not only the most active but are also capable of catalyzing this reaction with an unprecedented selectivity. In particular, in the presence of Bi(OTf)3, the targeted monoalkylglyceryl ethers were obtained with up to 70% yield. Although tested Bronsted acids were also capable of catalyzing the etherification of glycerol with alkyl alcohols, they were found however less active and less selective than Bi(OTf)3. By means of counter experiments, we highlighted that the high activity and selectivity of Bi(OTf)3 may rely on a synergistic effect between Bi(OTf)3 and triflic acid, a Bronsted acid that can be released by in situ glycerolysis of Bi(OTf)3. The scope of this methodology was also extended to other polyols and, in all cases, the monoalkylpolyol ethers were conveniently obtained with fair to good yields.
- Liu, Fei,De Oliveira Vigier, Karine,Pera-Titus, Marc,Pouilloux, Yannick,Clacens, Jean-Marc,Decampo, Floryan,Jerome, Francois
-
p. 901 - 909
(2013/07/26)
-
- PRODUCTION OF HYDROXY ETHER HYDROCARBONS BY LIQUID PHASE HYDROGENOLYSIS OF CYCLIC ACETALS OR CYCLIC KETALS
-
A liquid phase hydrogenolysis of acetal compounds such as cyclic acetals and cyclic ketals are fed to a reaction zone and reacted in the presence of a noble metal catalyst supported on a carbon or silica support to make hydroxy ether mono-hydrocarbons in high selectivity, without the necessity to use acidic co-catalysts such as phosphorus containing acids or stabilizers such as hydroquinone.
- -
-
Page/Page column 9-10
(2013/02/28)
-
- Tunable synthesis of propylene glycol ether from methanol and propylene oxide under ambient pressure
-
A series of basic and acidic ionic liquids, 1-butyl-3-methylimidazolium hydroxide (BMIMOH), 1-acetyl-3-methylimidazolium chloride (AcMIMCl) and AcMIMCl-FeCl3, or analogues of AcMIMCl, namely 1-potassium acetate-3-methylimidazolium chloride (KAcMIMCl), 1-potassium (sodium, ammonium) acetate-3-methylimidazolium hydroxides (KAcMIMOH, NaAcMIMOH and NH 4AcMIMOH), were prepared and used as catalysts for catalytic synthesis of propylene glycol ether via reaction of propylene oxide (PO) with methanol under mild reaction conditions. KAcMIMOH exhibited outstanding catalytic performance with 94.2% of conversion of PO and 99.1% of selectivity to 1-methoxy-2-propanol (MP-2) at 60°C and ambient pressure for 4 h. However, AcMIMCl-FeCl3 showed a good catalysis performance with high selectivity to 2-methoxy-1-propanol (MP-1). The tunable synthesis of MP-2 or MP-1 catalyzed by basic compound KAcMIMOH or acidic ionic liquid AcMIMCl-FeCl3 was realized.
- Bai, Yu,Cai, Qinghai,Wang, Xiaoguang,Lu, Bin
-
experimental part
p. 386 - 390
(2011/08/04)
-
- POLYOL ETHERS AND PROCESS FOR MAKING THEM
-
New polyol ether compounds and a process for their preparation. The process comprises reacting a polyol, a carbonyl compound, and hydrogen in the presence of hydrogenation catalyst, to provide the polyol ether. The molar ratio of polyol to carbonyl compound in the process is greater than 5:1.
- -
-
Paragraph 0072
(2011/05/14)
-
- POLYOL ETHERS AND PROCESS FOR MAKING THEM
-
New polyol ether compounds and a process for their preparation. The process comprises reacting a polyol, a carbonyl compound, and hydrogen in the presence of hydrogenation catalyst, to provide the polyol ether. The molar ratio of polyol to carbonyl compound in the process is greater than 5:1.
- -
-
Page/Page column 7-8
(2010/03/31)
-
- Cleavage of different ether bonds in butyl glycidyl ether and allyl glycidyl ether by K-, K+ (15-crown-5)2
-
The kind of substituent in alkyl glycidyl ethers affects the course of their reaction with K1, K+ (15-crown-5)2. The cyclic oxirane ring is exclusively cleaved in the case of butyl glycidyl ether whereas the presence of the unsaturated allyl group in the glycidyl ether molecule unexpectedly prefers the scission of the linear ether bond. In both the systems organometallic intermediates are formed. They react with crown ether causing its ring opening. Allylpotassium formed from allyl glycidyl ether reacts also with another glycidyl ether molecule; the oxirane ring is opened in this case.
- Grobelny, Zbigniew,Stolarzewicz, Andrzej,Maercker, Adalbert,Krompiec, Stanis?aw,Bieg, Tadeusz
-
p. 133 - 138
(2007/10/03)
-
- The Use of Proton-exchanged X-Type Zeolite in Catalysing Ring-opening Reactions of 2-Substituted Epoxides with Nucleophiles and its Effect on Regioselectivity
-
The use of proton-exchanged X-type zeolite in catalysing ring-opening reactions of 2-alkyl substituted epoxides with nucleophiles gives a high regioselectivity and functional-selective catalysis giving allylic products from allylic nucleophiles.Mechanistic aspects are discussed.
- Takeuchi, Hiroshi,Kitajima, Kunio,Yamamoto, Yasuhiro,Mizuno, Kiyokazu
-
p. 199 - 203
(2007/10/02)
-
- Lactic acid derivative and liquid crystal composition containing same
-
An optically active lactic acid derivative represented by the following formula (I): STR1 wherein R represents a linear, branched or cyclic saturated or unsaturated hydrocarbon group having 1 to 18 carbon atoms; C* represents an asymmetric carbon atom; l is 0 or 1; m is 1 or 2; A represents a group selected from the following groups (a) and (b): (a) hydroxyl group, halogen, benzyloxy group, phenoxy group, toluenesulfonic acid group, acetyloxy group, trifluoroacetyloxy group; STR2 (wherein R' is an alkyl group or alkoxy group having 4 to 18 carbon atoms, n is 0 or 1, STR3 with proviso that when A is selected from the groups in the above group (a), l is 1 and m is 1 or 2; and when A is selected from the groups in the above group (b), m=n=1 when l is 0, or m and n are 0, 1 or 2 and m+n is 1 or 2 when l is 1, and STR4
- -
-
-