Dimethyl sulfoxide as a solvent in the Williamson ether synthesis

1969 ◽  
Vol 47 (11) ◽  
pp. 2015-2019 ◽  
Author(s):  
Russel G. Smith ◽  
Alan Vanterpool ◽  
H. Jean Kulak
Keyword(s):  
Reaction Time ◽  
Dimethyl Sulfoxide ◽  
Butyl Alcohol ◽  
Major Product ◽  
Hydroxyl Groups ◽  
Reaction Products ◽  
Butyl Chloride ◽  
Butyl Ether ◽  
Ether Synthesis ◽  
Williamson Ether Synthesis

Using the conventional Williamson ether synthesis, n-butyl ether was prepared from sodium hydroxide, n-butyl alcohol, and n-butyl chloride using excess of the alcohol as solvent in 61% yield after 14 h reaction time. However, when the excess alcohol was replaced by dimethyl sulfoxide, the yield of ether rose to 95% with 9.5 h reaction time. Other primary alkyl chlorides exhibited similar behavior to n-butyl chloride, but secondary alkyl chlorides and primary alkyl bromides gave little etherification, elimination being the major reaction. Unreactive halides, such as vinyl chloride, phenyl bromide, and 2,4-dinitrobromobenzene, were not etherified in dimethyl sulfoxide. The reaction products obtained from aliphatic dichlorides depended upon the relative positions of the chlorine atoms. Secondary alcohols reacted to give ethers, but tertiary alcohols were very unreactive. Polyols generally gave high yields of ethers, the major product being that in which all but one of the hydroxyl groups became etherified. Under forcing conditions, however, completely etherified polyols could be obtained.

scholarly journals Effective synthesis of n-butyl salicylate over wash coated cordierite honeycomb by zirconia and its mixed oxides: a kinetic study

2018 ◽  
Vol 53 (1) ◽  
pp. 63-76
Author(s):  
M Shyamsundar ◽  
SZM Shamshuddin
Keyword(s):  
Reaction Time ◽  
Reaction Temperature ◽  
Methyl Salicylate ◽  
Mixed Oxides ◽  
Surface Acidity ◽  
Maximum Yield ◽  
Major Product ◽  
Transesterification Reaction ◽  
Molar Ratio ◽  
Butyl Ether

Cordierite honeycombs were coated with solid acid catalysts such as ZrO2 (Z), Mo(VI)/ZrO2 (MZ) and Pt-SO4 2-/ZrO2 (PSZ) were prepared and characterized for their physico-chemical properties. These catalytic materials were characterized for their total surface acidity, crystallinity, functionality, elemental analysis and morphology by using techniques such as NH3 -TPD, PXRD, FTIR, ICP-OES, SEM and TEM respectively. These honeycomb catalysts were used for the liquid phase transesterification reaction of methyl salicylate (MS) with n-butanol (n-BA). Optimization of reaction conditions such as reaction temperature, reaction time, amount of catalysts and molar ratio of the reactants were carried out to obtain maximum yield of transester (n-butyl salicylate). n-butyl salicylate is obtained as major product and di-butyl ether is obtained as minor product. Highest total transester 70 % obtained by MZ and 80 % n-butyl salicylate and 10 % selectivity of di-butyl ether obtained in the presence of 0.4 g of honeycomb coated catalysts at a molar ratio of MS: n-BA 2:1, reaction temperature 403 K and reaction time 4 h. The energy of activation (16.81 and 14.92 kJ mol-1) and temperature coefficient (1.36 and 1.12) values of the MZ and PSZ were obtained from the kinetic studies. Pre-adsorption studies showed that the transesterification reaction methyl salicylate with n-butyl alcohol over honeycomb catalysts follows Langmuir-Hinshelwood mechanism. A reaction mechanism for transesterification is proposed based on the kinetic data. Reactivation and reusability studies of the honeycomb coated as well as powder form of catalysts up to 6 reaction cycles were also studied.Bangladesh J. Sci. Ind. Res.53(1), 63-76, 2018

REACTIONS OF ALKOXY RADICALS: V. PHOTOLYSIS OF DI-t-BUTYL PEROXIDE

1958 ◽  
Vol 36 (9) ◽  
pp. 1227-1232 ◽  
Author(s):  
Garnett McMillan ◽  
M. H. J. Wijnen
Keyword(s):  
Activation Energy ◽  
Carbon Monoxide ◽  
Energy Difference ◽  
Butyl Alcohol ◽  
Reaction Products ◽  
Butyl Ether ◽  
Alkoxy Radicals ◽  
Temperature Range ◽  
Butyl Peroxide ◽  
Butoxy Radical

The photolysis of di-t-butyl peroxide has been investigated over the temperature range 25 ° to 79 °C. As reaction products were observed: acetone, t-butyl alcohol, methyl t-butyl ether, i-butylene oxide, ethane, methane, and carbon monoxide. The following reactions, involving the t-butoxy radical, have been studied:[Formula: see text]An activation energy difference of E2 − E6 = 3 kcal has been obtained.

ETHERIFICATION OF GLYCEROL AND BUTYL ALCOHOL USING SOLID CATALYST TO A PRODUCED GLYCEROL TERT-BUTYL ETHER (GTBE) (REVIEW OF THE EFFECT OF REACTION TIME AND THE NUMBER OF CATALYST ON THE SUCCESSED GTBE CONVERSION)

2019 ◽  
Vol 1 (2) ◽  
Author(s):  
Aulia Chania
Keyword(s):  
Reaction Time ◽  
Butyl Alcohol ◽  
Solid Catalyst ◽  
Fuel Additive ◽  
Butyl Ether ◽  
Tert Butyl

Eterifikasi gliserol dan tert-butil alkohol dengan katalis Dowex50WX2 dilakukan dengan menggunakan reaktor batch. Parameter penelitian yang divariasikan yaitu waktu reaksi 3jam, 4jam, dan 5jam serta jumlah katalis dengan variasi 7, 8 dan 9% berat. Penelitian ini bertujuan untuk memodifikasi gliserol menjadi fuel additive, mengetahui pengaruh waktu reaksi dan jumlah katalis Dowex 50WX2 terhadap konversi GTBE yang dihasilkan, dan mengetahui sifat fisik dan sifat kimia produk gliserol tert-butil eter yang dihasilkan dari reaksi eterifikasi. Hasil penelitian ini menunjukkan bahwa konversi gliserol terendah diperoleh pada waktu rekasi 3 jamdan jumlah katalis 7% berat yaitu 96,8043% , serta konversi gliserol tertinggi diperoleh pada waktu reaksi 5 jam dan jumlah katalis 8% berat yaitu 98,0362%.  sifat fisik dan sifat kimia produk berdasarkan analisis yang terlah dilakukan mendeskripsikan bahwa produk GTBE yang dihasilkan sesuai dengan standar fuel additive yang berlaku.

Base-catalyzed Dehydrobromination of Several α-Bromoacetals

1971 ◽  
Vol 49 (13) ◽  
pp. 2321-2335 ◽  
Author(s):  
H. A. Davis ◽  
R. K. Brown
Keyword(s):  
Ethylene Glycol ◽  
Dimethyl Sulfoxide ◽  
Marked Change ◽  
Butyl Alcohol ◽  
Major Product ◽  
Methine Proton ◽  
Ketene Acetal ◽  
Alkoxy Groups

Base-catalyzed dehydrohalogenation with potassium t-butoxide in t-butyl alcohol of the acetals obtained from homologues of α-bromoacetaldehyde and ethylene glycol[2-(α-bromoalkyl)-1,3-dioxo-lanes] or 1,3-propanediol[2-(α-bromoalkyl)-1,3-dioxane] provides the corresponding ketene acetal, in some cases exclusively and in others as the major product along with a smaller proportion of the α,β-unsaturated acetal. In contrast, similar dehydrohalogenation conditions convert the acetals obtained from homologues of α-bromoacetaldehyde and monohydroxy alcohols, to the α,β-unsaturated acetals, in some cases exclusively, and in others as the major product accompanied by a smaller proportion of the corresponding ketene acetal.The preference for the ketene acetal formation from the 2-(α-bromoalkyl)-1,3-dioxolanes (the ethyleneacetals) is believed due to greater ease of approach by base to the methine proton as a result of the restricted shape of the 1,3-dioxolane ring. Approach by base to the methine proton of the α-bromoalkyl dialkylacetals is more hindered by the two alkoxy groups, which cause preferred attack by base at the β proton to provide the α,β-unsaturated acetal.The proportion of α,β-unsaturated acetal obtained from base-catalyzed dehydrohalogenation of 2-(α-bromoalkyl)-1,3-dioxolanes can be greatly increased if the reaction is carried out in dimethyl sulfoxide. This marked change in proportion of products is thought to be due to a change in mechanism occasioned by the dimethyl sulfoxide.

HSCCC Separation of Three Main Compounds from the Crude Extract of Dracocephalum Tanguticum by Using Dimethyl Sulfoxide as Cosolvent

2020 ◽  
Author(s):  
Xue Yang ◽  
Yongling Liu ◽  
Tao Chen ◽  
Nana Wang ◽  
Hongmei Li ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Ethyl Acetate ◽  
Dimethyl Sulfoxide ◽  
Efficient Method ◽  
Crude Extract ◽  
High Speed ◽  
Glacial Acetic Acid ◽  
Butyl Alcohol ◽  
Preparative Hplc ◽  
Counter Current

Abstract Separation of natural compounds directly from the crude extract is a challenging work for traditional column chromatography. In the present study, an efficient method for separation of three main compounds from the crude extract of Dracocephalum tanguticum has been successfully established by high-speed counter-current chromatography (HSCCC). The crude extract was directly introduced into HSCCC by using dimethyl sulfoxide as cosolvent. Ethyl acetate/n-butyl alcohol/0.3% glacial acetic acid (4: 1: 5, v/v) system was used and three target compounds with purity higher than 80% were obtained. Preparative HPLC was used for further purification and three target compounds with purity higher than 98% were obtained. The compounds were identified as chlorogenic acid, pedaliin and pedaliin-6″-acetate.

scholarly journals Biodegradation of Methyl tert-Butyl Ether and Other Fuel Oxygenates by a New Strain, Mycobacterium austroafricanum IFP 2012

2002 ◽  
Vol 68 (6) ◽  
pp. 2754-2762 ◽  
Author(s):  
Alan François ◽  
Hugues Mathis ◽  
Davy Godefroy ◽  
Pascal Piveteau ◽  
Françoise Fayolle ◽  
...  
Keyword(s):  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Dry Weight ◽  
Butyl Alcohol ◽  
Amyl Alcohol ◽  
Methyl Tert Butyl Ether ◽  
Methylotrophic Bacterium ◽  
Specific Rate ◽  
Butyl Ether ◽  
Mycobacterium Austroafricanum

ABSTRACT A strain that efficiently degraded methyl tert-butyl ether (MTBE) was obtained by initial selection on the recalcitrant compound tert-butyl alcohol (TBA). This strain, a gram-positive methylotrophic bacterium identified as Mycobacterium austroafricanum IFP 2012, was also able to degrade tert-amyl methyl ether and tert-amyl alcohol. Ethyl tert-butyl ether was weakly degraded. tert-Butyl formate and 2-hydroxy isobutyrate (HIBA), two intermediates in the MTBE catabolism pathway, were detected during growth on MTBE. A positive effect of Co2+ during growth of M. austroafricanum IFP 2012 on HIBA was demonstrated. The specific rate of MTBE degradation was 0.6 mmol/h/g (dry weight) of cells, and the biomass yield on MTBE was 0.44 g (dry weight) per g of MTBE. MTBE, TBA, and HIBA degradation activities were induced by MTBE and TBA, and TBA was a good inducer. Involvement of at least one monooxygenase during degradation of MTBE and TBA was shown by (i) the requirement for oxygen, (ii) the production of propylene epoxide from propylene by MTBE- or TBA- grown cells, and (iii) the inhibition of MTBE or TBA degradation and of propylene epoxide production by acetylene. No cytochrome P-450 was detected in MTBE- or TBA-grown cells. Similar protein profiles were obtained after sodium dodecyl sulfate-polyacrylamide gel electrophoresis of crude extracts from MTBE- and TBA-grown cells. Among the polypeptides induced by these substrates, two polypeptides (66 and 27 kDa) exhibited strong similarities with known oxidoreductases.

scholarly journals Tuning the Reaction Selectivity over MgAl Spinel-Supported Pt Catalyst in Furfuryl Alcohol Conversion to Pentanediols

Catalysts ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 415
Author(s):  
Xinsheng Li ◽  
Jifeng Pang ◽  
Jingcai Zhang ◽  
Xianquan Li ◽  
Yu Jiang ◽  
...  
Keyword(s):  
Furfuryl Alcohol ◽  
Pt Nanoparticles ◽  
Catalytic Performance ◽  
Major Product ◽  
Pt Catalyst ◽  
Reaction Products ◽  
Strong Base ◽  
Reaction Selectivity ◽  
Supported Pt Catalysts ◽  
Alcohol Conversion

Catalytic conversion of biomass-derived feedstock to high-value chemicals is of remarkable significance for alleviating dependence on fossil energy resources. MgAl spinel-supported Pt catalysts were prepared and used in furfuryl alcohol conversion. The approaches to tune the reaction selectivity toward pentanediols (PeDs) were investigated and the catalytic performance was correlated to the catalysts’ physicochemical properties based on comprehensive characterizations. It was found that 1–8 wt% Pt was highly dispersed on the MgAl2O4 support as nanoparticles with small sizes of 1–3 nm. The reaction selectivity did not show dependence on the size of Pt nanoparticles. Introducing LiOH onto the support effectively steered the reaction products toward the PeDs at the expense of tetrahydrofurfuryl alcohol (THFA) selectivity. Meanwhile, the major product in PeDs was shifted from 1,5-PeD to 1,2-PeD. The reasons for the PeDs selectivity enhancement were attributed to the generation of a large number of medium-strong base sites on the Li-modified Pt catalyst. The reaction temperature is another effective factor to tune the reaction selectivity. At 230 °C, PeDs selectivity was enhanced to 77.4% with a 1,2-PeD to 1,5-PeD ratio of 3.7 over 4Pt/10Li/MgAl2O4. The Pt/Li/MgAl2O4 catalyst was robust to be reused five times without deactivation.

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