Hydration Of Alcohols Research Articles

Hydration of Propargylic Alcohols by Ruthenium Catalysts, with Dominant Anti‐Markovnikov Regioselectivity, Formation of α,β‐Unsaturated Products and Catalytic Decarbonylation to 1‐Alkenes

AbstractRuthenium catalysts — water‐soluble ruthenium sulfophthalocyanine and heterogeneous ruthenium hydroxyapatite complexes — proved to be effective for the hydration of propargylic alcohols in entirely aqueous media. 1‐Phenyl‐2‐propyn‐1‐ol underwent an unprecedented catalytic hydration‐decarbonylation‐dehydration reaction, giving rise to styrene and carbon monoxide; 2‐propyn‐1‐ol and 3‐butyn‐2‐ol gave predominantly the products of anti‐Markovnikov addition, together with products of hydration‐dehydration (α,β‐rearrangement) and, to a minor extent, the decarbonylation products, ethene or propene, respectively. Hydrations were also conducted in D2O, giving indications of the mechanism of the reactions and apparently ruling out the allenylidene route for the α,β‐rearrangement. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)

Evolution of Organized Lariat Ether Alcohol and Diol Hydrate Macrostructures in the Solid State

Lariat ether alcohols and diols derived from dibenzo-14-crown-4crystallize in the anhydrous form or as hydrogen-bondedmonohydrates or networks depending upon thepolyether ring substitutents and the composition of the aqueous organic crystallization solvent. Supramolecular structures are created when the lariat ether alcohol sym-(hydroxy)dibenzo-14-crown-4 (1) with ``sticky ends'' of ether oxygens and hydroxyl protons, hydrogen bond to each other via bridging water molecules to form three-dimensional networks. For crystallization of 1 from 30% aqueous acetonitrile, this self-association is sufficiently strong to spontaneously generate a supramolecular structure with water channels.

Asymmetric hydration of allyl alcohol catalyzed by polysulfostyrene– gelatin–Co complex

A new chiral polymer–metal complex, polysulfostyrene–gelatin–cobalt complex (PSS–GE–Co) has been prepared and found to be able to catalyze the asymmetric hydration of allyl alcohol to give (S)-(−)-1,2-propanediol in 98% yield with 98.9% optical yield. The catalyst is very stable and can be reused without any remarkable effect in catalytic activity and optical selectivity. Copyright © 2002 John Wiley & Sons, Ltd.

Asymmetric hydration of allyl alcohol catalyzed by polysulfostyrene– gelatin–Co complex

AbstractA new chiral polymer–metal complex, polysulfostyrene–gelatin–cobalt complex (PSS–GE–Co) has been prepared and found to be able to catalyze the asymmetric hydration of allyl alcohol to give (S)‐(−)‐1,2‐propanediol in 98% yield with 98.9% optical yield. The catalyst is very stable and can be reused without any remarkable effect in catalytic activity and optical selectivity. Copyright © 2002 John Wiley & Sons, Ltd.

Hydrophobic hydration of tert-butyl alcohol probed by NMR and IR

The hydrophobic hydration in aqueous tert-butyl alcohol(TBA) mixtures was studied by examining the concentration and the temperature dependences of 1H and 13C chemical shifts in NMR, together with the concentration dependence of the frequency for the CH stretching vibration band, νCH. The chemical shifts were measured with the external double reference method, with which the bulk volume magnetic susceptibility for every sample mixture was also obtained to be used for the correction of the chemical shifts in situ. The polarization of the water molecules in the mixture probed by the 1H chemical shift, ∗δH2O, varies with concentration; δH2O increases at 23.3°C from 3.5 ppm in the TBA-rich region to the value for pure water at the mole fraction of water χW=0.84 and reaches to the maximum at χW=0.95. In the region of 0.84<χW<1.0, δH2O is larger than that for pure water, indicating clearly the presence of highly polarized or strongly hydrogen-bonding water molecules compared with pure water. The νCH also continues to increase with increasing χW from 2973.6cm−1 for pure TBA gently up to χW=0.84 and then steeply up to χW=0.95 to reach 2980.3cm−1, then remains constant up to the measurable concentration limit, χW=0.99. The polarization of TBA molecule was also found to increase in the same way as νCH. These results not only indicate the formation of associated complexes of TBA with water molecules, but also confirm the formation of polyhedron or cluster so far presented for mixing state in water-rich region. In addition to this the results show that the hydration of CH groups occurs through a kind of dispersion interaction between CH group and water oxygen, in which contraction of the CH bond occurs as demonstrated by the blueshifts of the CH stretching vibration band. The new mechanism of CH hydration, termed “push ball” hydration, is proposed.

Dynamics of hydration of alcohols and diols in aqueous solutions

The 17 O NMR spin–lattice relaxation times, T 1 , of the solvent water in aqueous solutions of nine alcohols and five diols have been determined as a function of the concentration at 25°C. For the alcohol solutions, the concentration dependence of T 1 has been determined in the temperature range from 1 to 50°C. The value of n h [(τ c h / τ c 0 )-1] which has been obtained from the concentration dependence of T 1 has been defined as the dynamic hydration number (n DHN ). The values of the coordination numbers n h , have been estimated on the basis of the water-accessible surface areas (ASA) of the solute molecules. The rotational correlation times, τ c h , of water molecules around the solute molecules have been estimated and compared with that of pure water τ c 0 . The value of τ c h /τ c 0 =2.22 for Bu t OH at 25°C is the largest among the solutes investigated. The τ c h /τ c 0 values of the n-alcohols and diols increase with increasing ASA and become almost constant. The τ c h /τ c 0 values decrease with increasing temperature and approach constant value above 40°C. The temperature dependence of τ c h /τ c 0 for Bu t OH is the largest. The activation energy of τ c h for n-alcohols has the maximum value at ASA≈240 A 2 . These results are discussed by considering the molecular sizes. The τ c h /τ c 0 value for a diol was smaller than that of the corresponding n-alcohol. This result supports the concept that hydrophobic hydration is distributed by the OH groups of the solute molecules. The thermodynamic properties of hydration for n-alcohols, butanol isomers and diols are linearly dependent on their n DHN .

Stability of polar guest-encaging clathrate hydrates

In order to account for the experimental observation that some amines form clathrate hydrates but that alcohols inhibit hydrate formation, we investigate the stability of clathrate hydrates which encage highly polar guest molecules by examining potential energy local minimum structures and also thermally excited structures. First, we examine the local minimum structure at which the total potential energy has a minimum value for amine and alcohol hydrates and inquire whether, in the absence of thermal fluctuations, the conditions for true-clathrate hydrates are satisfied. The local minimum structures of alcohol hydrates are distinguished from those of stable clathrate hydrates of structures I and II, while amine hydrates hold the host lattice of clathrate hydrates. We argue that the difference between the magnitude of the partial charge on the hydrogen atom of the hydroxyl and amino groups plays a much more significant role in the stability of both kinds of clathrate hydrates than the difference in molecular geometry does. Second, we examine kinetic stability by molecular dynamics simulation. Near room temperature the host lattice structure encaging amine remains intact. This is in contrast to the alcohol hydrate, which begins to melt easily with thermal excitation. Interesting is the finding that very long-time-scale (∼100 ps) fluctuations of the host potential energy is observed, as well as fast oscillations caused by temporary partial defects in the host network. Clathrate hydrates of polar guest molecules may experience an unstable state in which the host hydrogen-bonded network is partially broken and guest–host hydrogen-bond generation occurs but the stable state of their host lattices is again restored.

Hydration of acetylenic compounds without using mercury

Copper(II), palladium(II) and silver(I), in conjunction with non-coordinating anion environments, have been found to catalyze the hydration of a variety of functionalized and nonfunctionalized alkynes. Suitable anions include trifluoromethane sulfonate, tetrafluoroborate, and sulfonate groups on perfluorinated ion-exchange resins. These catalyst systems are the first reported catalysts that are active for the hydration of acetylenic alcohols in high selectivity and do not contain mercury. The problems of dehydration and byproduct formation, observed when other catalysts are used with these alcohols, are minimized.

Structures of a pair of diastereomeric salts of ephedrine and fluoro-substituted cyclic phosphoric acid

(1) (R)-(+)-4-(2,6-Dichlorophenyl)-2-hydroxy-5,5-dimethyl-1,3,2-dioxaphosphorinane 2-oxide (1S,2R)-(-)-alpha-[(1-methylamino)ethyl]benzyl alcohol, (-)-C10H16NO+.(+)-C11H12Cl2O4P-, M(r) = 476.335, monoclinic, P2(1), a = 10.063(1), b = 8.206(1), c = 14.856(1) angstrom, beta = 104.84(1)-degrees, V = 1185.8 (2) angstrom3, Z = 2, D(x) = 1.334 Mg m-3, Mo K-alpha radiation (graphite monochromator), lambda = 0.71073 angstrom, mu(Mo K-alpha) = 0.3689 mm-1, F(000) = 500, T = 130 K, final R = 0.053, wR = 0.056 for 3504 observed unique reflections and 281 variables. (2) (S)-(-)-4-(2,6-Dichlorophenyl)-2-hydroxy-5,5-dimethyl-1,3,2-dioxaphosphorinane 2-oxide (1R,2S)-(-)-alpha-[(1-methylamino)ethyl]benzyl alcohol hydrate, (-)-C10H16NO+.(-)-C11H12Cl2O4P-.H2O, M(r) = 494.351, orthorhombic, P2(1)2(1)2(1), a = 6.502(1), b = 11.393 (1), c = 32.739 (1) angstrom, V = 2425.2 (4) angstrom3, Z = 4, D(x) = 1.354 Mg m-3, Mo K-alpha radiation (graphite monochromator), lambda = 0.71073 angstrom, mu-(Mo K-alpha) = 0.3660 mm-1, F(000) = 1040, T = 130 K, final R = 0.055, wR = 0.059 for 4225 observed unique reflections and 265 variables. For both (1) and (2), the phosphorinane ring is in the usual chair conformation and the ephedrine is in an extended form. The crystal packing of (1) can be regarded as chains parallel to the b axis consisting of phosphorinane anions and ephedrine cations linked by hydrogen bonds. In the crystal packing of (2), which can also be regarded as chains parallel to the b axis, the solvent water molecules are incorporated in the hydrogen-bonding pattern between the phosphorinane and ephedrine ions.

Millimeter spectroscopic study of intermolecular interactions in solutions

The absorption of 5 cm−1 electromagnetic radiation by aqueous solutions of methyl, ethyl, n-, and isopropyl, sec-, iso-, and tert-butyl, and tert-amyl alcohols and ethylene glycol was measured within their solubility limits in water at 20°C. It was found that the observed nonadditivity of absorption (absorption deficit) is a qualitative measure of hydration of alcohols of two types: hydrophilic and hydrophobic. The possibility of distinguishing these effects by millimeter spectroscopy was demonstrated. Hydrophobic hydration makes the basic contribution to the hydration number of aliphatic alcohols. On the example of solutions of ethanol and tert-butanol, it was shown that hydrophobic hydration decreases with an increase in the temperature of the solution due to intensification of hydrophobic interactions between the hydrocarbon radicals.

Molecular dynamics simulations on the hydration of fluoroalcohols

Molecular dynamics (MD) calculations have been carried out for aqueous solutions of isopropyl alcohol (IPA) and its fluorinated compounds, 1,1,1-trifluoro-2-propanol (TFIPA) and 1,1,1,3,3,3-hexafluoro-2-propanol (HFIPA). The simulated systems were canonical ensembles containing 216 molecules in each, one of which was alcohol and the temperature was set to 298.15 K. The MCY (Matsuoka–Clementi–Yoshimine) potential was used for water–water interaction, whereas new potential functions were determined for alcohol–water interactions, on the basis of ab initio molecular orbital calculations on more than 1100 different dimeric configurations for each alcohol–water pair. The static properties of solvent water in the vicinity of each functional group of solute were obtained from MD calculations. It is found that the promotion of water structure and the increase of hydrogen bond between water molecules occurs not only near the fluoroalkyl group but also even near hydroxyl group of fluoroalcohols. Furthermore, the alcohol–water interaction is stronger for fluoroalcohols than for aliphatic alcohols, owing to the electronegativity and the electron withdrawing effect of fluorine atoms. The enthalpies of hydration for fluoroalcohols include the contributions from these features of both water–water and alcohol–water interactions. This is not the case for the hydration of aliphatic alcohols, and is the reason for the lack of regular change of enthalpies of hydration with the degree of the substitution of CH3 by the CF3 group. The hydration of IPA is similar to that of other aliphatic alcohols; hydrophobic hydration near the apolar group and the energetic unstabilization of water near the hydroxyl group are observed.

Hydration of alcohols by ultrasonic velocity measurements in ternary systems

Ultrasonic velocity maxima have been determined as a function of alcohol (methanol, ethanol, n-propanol or t-butanol) concentration in ternary aqueous alcoholic solutions of a number of mono- and polyhydroxyalcohols. The location of the maxima relative to those in the binary water-alcohol systems are related to the hydration of the solute molecule. It is established that correlations between the extent of hydration and some structural parameters of the solute molecules are of the same character in all binary solvents studied.

Hydration of allenylacetylenic alcohols ? New route to 6-methyl-2,3-dihydro-4-pyranones

The mercuric sulfate-catalyzed acidic hydration of allenylacetylenic alcohols leads to 6-methyl-2,3-dihydro-4-pyranones — products of cyclization of unsaturated β-diketones. In the case of 1-(3,4-pentadien-1-ynyl)cyclohexanol 2-(1-cyclohexenyl)-5-methylfuran is formed in addition to the corresponding dihydropyranone.

Hydration of alcohols in aqueous methanol solutions from ultrasonic velocity measurements

Ultrasonic velocity maxima, as a function of alcohol concentration in aqueous methanol solution, have been determined for solutions of a number of mono- and polyhydroxyalcohols. The location of the maximum relative to that in the water-methanol system alone was related to the hydration of the solute molecule. Calculated hydration numbers are linearly correlated with the number of hydroxyl groups in the case of polyhydroxyalcohols, and with the surface area of the non-polar regions in the case of monohydroxyalcohols.

Hydrates of Organic Compounds. V. The Clathrate Hydration of Alcohols

Abstract A new method for examining the ability of a given substance to form a hydrate with the same structure as that of a reference substance has been established. By using this method, for a series of alcohols ranging from methyl alcohol to pentyl alcohol, including their isomers, the ability to form a clathrate hydrate of either Structure I or Structure II has been investigated. It has been found that: (1) methyl alcohol has the ability to form both Structure I and II hydrates; (2) ethyl alcohol has the ability to form a Structure II hydrate; (3) all C3-alcohols (propyl, isopropyl, allyl, and propargyl alcohol) can actually form Structure II hydrates with relatively high (around −10 °C) incongruent melting points, and (4) among the C4- and C5-alcohols, only t-butyl alcohol has the ability to form a Structure II hydrate. However, it is uncertain for methyl and ethyl alcohols whether they actually can form such hydrates even in the absence of a reference substance. These results strongly suggest that the size and/or shape limitation plays an important role in the formation of alcohol hydrates with a gas-hydrate structure, just as has been found for the formation of ether and ketone hydrates.

Kinetics and the mechanism of isoamylene alcohol conversion in acid media containing formaldehyde

Isoamylene alcohols (3-methyl-3-butene-3-ol, I; 3-methyl-1-butene-3-ol, II) in aqueous acid solutions (H 2SO 4, HClO 4) were subjected to reducible isomerization, hydration to 3-methyl-butane-l, 3-diol (III) and dehydration to isopropene (C 5H 8). The kinetics and mechanism of these reactions were studied in detail [1, 2]. The unsaturated alcohols I and II and glycol III in acid solutions containing formaldehyde (CH 20) are known to react with CH 20 to form multiple condensation products [3, 4]. We studied the kinetics of isopropene hydration (reaction 1) to an equilibrium mixture of alcohols I and II, the hydration of alcohols I and II (2), and the condensation of com pounds I, II, III with CH 2O (3) in various solutions of sulphuric and chloric acids, varying the content of CH 20 from 0 to 1.0 mole/l at 25 and 40 °C [5]. The observed rate constants of reactions (1), (2), (3) were found to depend on the acid concentration and at the given medium acidity on CH 20 concentration in the system. The reaction mechanisms are discussed in terms of the kinetic regularities obtained. The catalytic activity of formaldehyde is controlled by the medium acidity (h o) and the concentration of nucleophiles (HSO − 4, ClO − 4).

Total Syntheses of Carbohydrates. I. Dihydroxyacetone and Dl-Erythrulose

Abstract An improved method of preparation of halopropargyl alcohol is described. Hydration of halopropargyl alcohol followed by hydrolysis gave dihydroxyacetone which was identified as its dibenzoate. 2-Butyne-1,4-diol was converted into acetoxymethyl vinyl ketone. 1,4-Diacetoxy-3-bromobutan-2-one obtained by the addition of acetyl hypobromite to the vinyl ketone was treated with silver acetate to yield tri-O-acetyl-Dl-erythrulose. Hydrolysis of the triacetate afforded Dl-erythrulose which was identified as phenylhydrazone.

Hydration of primary alcohols

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTHydration of primary alcoholsHans SchottCite this: J. Chem. Eng. Data 1969, 14, 2, 237–239Publication Date (Print):April 1, 1969Publication History Published online1 May 2002Published inissue 1 April 1969https://doi.org/10.1021/je60041a004RIGHTS & PERMISSIONSArticle Views80Altmetric-Citations21LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (286 KB) Get e-Alerts Get e-Alerts

Measurement of the velocity distribution in a plasmajet.

Accordingly, heat of reaction with mixed acid, RFNA and oleum were estimated separately for various alcohols. These are given in Table 4. The measured values of heat of reac- tion for different alcohols are compared with the value ex- pected if both the side reactions proceeded proportional to the amount of oleum and RFNA in the mixed acid. The comparison shows that the amount of alcohol used in the two simultaneous side reactions is in proportion to the amounts of respective acids. The small difference in the values may be caused by the other side reactions. The case for butanols needs further investigation. The reaction (2) probably takes place in two stages The heat of reaction for stage (a) is recorded in Table 4 which is much smaller than heat produced during the reaction of ethyl alcohol with RFNA. The heat of reaction with mixed acid is a little higher than the calculated values, showing that probably more side reactions occur. No simple correlation exists between the ignitability and the structure. The ignition involves two processes, viz., (a) oxidation (b) dehydration to form alkene. Normal alcohols are most easily oxidized whereas tertiary alcohols are most easily dehydrated. During the reaction, oxidation and de- hydration of alcohols occur simultaneously; hence, no order in the values of heat of reaction is found. The reaction would depend presumably on the nature of the reactivity of corresponding alkenes towards N02 and on the nature of oxidation products of various alcohols. From Table 3 it appears that calcium and potassium per- manganates are good catalysts for ignition. This probably may be caused by production of atomic oxygen that acceler- ates the oxidation of alcohols.3 The heats of ignition with pot- assium permanganate as an additive have been measured also for various alcohols (Table 5). The values are consistently much higher as compared to the case when no additive is added. Presumably more side reaction or consecutive reactions take place in the latter case.

The Porous Structure of Active Carbons. X. The De. hydration of Alcohols in the Presence of Active Carbons. Part I.

前報で活性炭素とイソプロピルアルコール轍相(常温)または気相(200℃)で接触させるとアルコールが脱水され,レンが生ずることを報告した。本報ではさらにこの現象を究めるために,前報と同じ活性炭素SZ4,S4を用い,これプらロにピ比較的低温(210° ～310℃)でアルコール蒸気を接触させつぎの結果を得た。k(1)第一アルコ0ルは変化しないがi第二,第三アルコールは脱水作用をうけてそれぞれのオレフィンになる。(2)これらの脱水反応における見かけの活性化エネルギーは吸着熱の大きさと逆の順序になっている。(3)脱水反応の活性中心は吸着媒の酸性基の部分である。(4)吸着媒の細孔径の大きさによって律速残階の過程が異なってくる。