Addition of tetrachloromethane to oct-1-ene initiated by amino alcohols

The kinetics and mechanism of an addition of CCl₄ to oct-1-ene initiated by amines, aromatic alcohols, and amino alcohols (structural analogs of ephedrin) were studied. The radical mechanism of the reaction was established by ESR using the technique of spin traps. Aromatic amino alcohols as initiators are more active than amines and aromatic alcohols of similar structure. They are more selective compared to the amines and aromatic alcohols and react with CCl₄ already at room temperature to form predominantly benzaldehyde. The scheme of initiation by aromatic amino alcohols of the addition of CCl₄ to olefins was proposed on the basis of the experimental data. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1565–1571, September, 2006.     

A stereodivergent approach to 1-deoxynojirimycin, 1-deoxygalactonojirimycin and 1-deoxymannojirimycin derivatives

A stereodivergent synthesis of N-alkylated 1-deoxygalactonojirimycin and 1-deoxymannojirimycin derivatives has been achieved from a protected 1-deoxynojirimycin intermediate having two free OH groups tactically positioned at C-2 and C-4. The inversion of configuration of the secondary alcohols was performed by way of a Swern oxidation followed by a highly diastereoselective reduction using NaBH₄ or L-Selectride.     

Palladium-catalysed oxidation of alcohols with carbon tetrachloride,formation of 4,4,4-trichloro ketones from allylic alcohols and carbon tetrachlorid

Pd salts catalyse oxidation of alcohols with CCl₄ in the presence of K₂CO₃. Primary alcohols are oxidised to esters, and secondary alcohols to ketones. CCl₄ is converted to CHCl₃. The reaction of allylic alcohols bearing a terminal olefinic bond with CCl₄ or BrCCl₃ in the presence of palladium catalyst at 110° affords 4,4,4-trichloro ketones. At 40°, simple adducts of CCl₄ or BrCCl₃ having a halohydrin structure are obtained, which are converted to the corresponding trichloro ketones by the catalysis of palladium. Various halohydrins are converted to ketones by Pd catalysis.     

A kinetic study of the mechanism of esterification of 1-arylethanols in trifluoroacetic acid

Aryl substituent effects upon the rate constants for the esterification of a series of 1-arylethanols in trifluoroacetic acid are in accordance with a reverse A_AL1 mechanism, for which the Hammett reaction constant ? = ?3.69 has been determined by correlation with σ⁺ substituent constants. The rates of reaction are ca. 50-fold faster than those for corresponding benzyl alcohols which bear an electron-donating aryl substituent and which are also believed to undergo esterification in trifluoroacetic acid by the reverse A_AL1 mechanism; the reverse A_AC2 mechanism applies to benzyl alcohols which bear an electron- withdrawing aryl substituent.     

Distribution coefficients in the water-dodecane system and the heats of adsorption of C<Subscript>1</Subscript>-C<Subscript>8</Subscript> alcohols on silica

Distribution coefficients in the water-dodecane system and the heats of adsorption of C₁-C₈ alcohols on silica (Silochrom S-80) were determined by gas chromatography. At low temperatures, C₁-C₄ alcohols were largely distributed in the aqueous phase, and C₆-C₉ alcohols were predominantly dissolved in the organic phase; C₅ alcohols had intermediate properties. Permittivity was found to correlate with log K _d, which allowed us to predict the character of the distribution of alcohols in the water-oil system. The heats and isotherms of adsorption were determined for the alcohols studied. The heats of adsorption of alcohols on silica monotonically increased in the series under consideration. For C₅-C₈ alcohols, they exceeded the heat of adsorption of water. The isotherms of adsorption were described by the Freundlich equation.     

Formation of stable carbenoid α-methoxyorganolithium compounds, 1-alkyl-2-lithiummethoxymethyl-o-carboranes,by metalation of 1-alkyl-2-methoxymethyl-o-carboranes withn-butyllithium

1-Alkyl-2-methoxymethyl-o-carboranes are easily metalated withn-butyllithium in an ether-benzene solution to form carbenoid 1-alkyl-2-lithiummethoxymethyl-o-carboranes, which are stable at room temperature. Under the action of H₂O, CO₂, and PhCHO these lithium carboranes yield the starting compounds, carboxylic acids, and benzyl alcohols, respectively.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 243–245, January, 1996.     

CO2 Conversion with Alcohols and Amines into Carbonates,Ureas, and Carbamates over CeO2 Catalyst in the Presence and Absence of 2‐Cyanopyridine

Recent progress on the CeO₂ catalyzed synthesis of organic carbonates, ureas, and carbamates from CO₂+alcohols, CO₂+amines, and CO₂+alcohols+amines, respectively, is reviewed. The reactions of CO₂ with alcohols and amines are reversible ones and the degree of the equilibrium limitation of the synthesis reactions is strongly dependent on the properties of alcohols and amines as the substrates. When the equilibrium limitation of the reaction is serious, the equilibrium conversion of the substrate and the yield of the target product is very low, therefore, the shift of the equilibrium reaction to the product side by the removal of H₂O is essential in order to get the target product in high yield. One of the effective method of the H₂O removal from the related reaction systems is the combination with the hydration of 2‐cyanopyridine to 2‐picolinamide, which is also catalyzed by CeO₂.     

Carbonylation of Polyfluorinated 1-Arylalkan-1-ols and Diols in Superacids

We describe the carbonylation of a series of mono and dihydroxy derivatives of polyfluorinated alkylbenzenes and benzocycloalkenes with OH groups at benzylic positions using carbon monoxide in the presence of a superacid (TfOH, a TfOH–SbF₅ mixture, or a FSO₃H–SbF₅ mixture). It was shown that the superacid-catalyzed addition of CO to various primary and secondary polyfluorinated alcohols and diols gives the corresponding mono- and dicarboxylic acids or lactones. The efficiency of various superacids depending on alcohol structure was evaluated, and FSO₃H–SbF₅ yielded the best results in most transformations. The addition of CO to secondary 1-arylalkan-1-ols containing vicinal fluorine atoms was found to be accompanied by elimination of HF with the formation of α,β-unsaturated aryl-carboxylic acids. In contrast to primary and secondary alcohols, conversion of tertiary perfluoro-1,1-diarylalkan-1-ols into carbonylation products is not complete, and the resulting carboxylic acids are easily decarboxylated after water treatment of the reaction mixture.     

Thermodynamics of the Solubility of Water in 1-Hexanol, 1-Octanol, 1-Decanol, and Cyclohexanol

Summary. The solubility of water in 1-hexanol, 1-octanol, 1-decanol, and cyclohexanol was determined as a function of water activity by the isopiestic method at 298.2K. The solubility of water in the alcohol was expressed by a Setchenov type of equation and the correlation coefficients were related to the virial coefficients of the McMillan-Mayer theory of solution. From the solubility data both the activities and the osmotic coefficients of the alcohols were calculated. The Henrys law constants for the solubility of water in the alcohols are given. They depend linearly on the Gibbs energy of hydration. The excess Gibbs energy of mixing of water and alcohols is positive as a consequence of the strong intermolecular interactions of the two pure components of the mixture.     

Catalytic transformations of 1-octanol and 2-ethyl-1-hexanol over oxide catalysts, 1. Transition metal oxides as catalysts

A comparative study of 1-octanol and 2-ethyl-1-hexanol transformations over silica supported NiO, MnO₂, Cr₂O₃, Fe₂O₃, and ZnO has been performed. Zinca containing catalyst was found to be the most active in dehydrogenation and dehydration of the alcohols studied. ZnO dehydrogenating activity increased with supported oxide load.     

Significant Heterogeneous Carbonate Salt Catalyzed Acetylation of Alcohols via a Transesterification Process with Carbonate Salt‐activated Alcohol 1H NMR Evidence

Heterogeneous carbonate salt catalyzed acetylation of alcohols via a transesterification process has been developed. Various esters are furnished up to 97% yield. Established procedure is simple and air‐tolerant with readily available reagents. Ethyl acetate and isobutyl acetate are used as not only acetylating agents, but also reaction solvents in transesterification. Aliphatic linear alcohols, allylic alcohols and benzyl alcohols show high reactivities in the presence of 1 or 5 mol% Cs₂CO₃ at 125°C. Cesium carbonate can be recycled by pumping liquid phase out of reactor after reaction. During four cycle runs for reaction of 2‐phenylethanol and ethyl acetate, high yields of phenethyl acetate are provided (>60% yield). Based on experiments and ¹H NMR investigation, bifunctional catalysis is proposed, alcohol activated by carbonate ion is confirmed, and higher activity of catalytic amount than stoichiometric cesium carbonate is interpreted.     

Snytheses and Reactions of O,N,N′-Trisubstituted Isoureas

The CuCl₂-catalysed addition of alcohols to aliphatic caribodiimides (particularly diisopropylcarbodiimide) to form O,N,N′-trialkylisoureas may, in the case of bifunctional hydroxy compounds (esters of α-hydroxycarboxylic acids, diols, halogeno alcohols, amino alcohols, and cyclic hydroxy ethers), continue to give 5-, 6-, and 7-membered 1,3-O,N or 1,3-N,N heterocycles. O,N,N′-Trialkylisoureas are selective alkylating agents. Thus alcohols with allyl structures can be etherified with diisopropylcarbodiimide; a new method of esterification via O,N,N′-trialkylisoureas has been applied to mesitylenecarboxylic acid.     

Iron Perchlorate on Silica Gel as Multi-purpose Reagent for Catalysis of Closure and Rupture of Carbon-Oxygen Bond in Epoxides,Alcohols, and Esters

Aliphatic alcohols and water in the presence of catalytic amounts of Fe³⁺ ion introduced as acids esterification with various type alcohols was carried out using the system Fe(ClO₄)₃-silica gel in dichloromethane under conditions excluding solvolysis. Acetylation and formylation of alcohols was performed by efficient transesterification with ethyl acetate and ethyl formate.     

New silicon-containing heterocyclic rings derived from 1, 3-bis(methyldichlorosilyl)propane

Reaction of 1,3-bis(methyldichlorosilyl)propane with alcohols gives (methylalkoxychlorosilyl)propanes. Hydrolysis of the latter with the calculated amount of water in the presence of a HCl acceptor gives 2, 6-dimethyl-2,6-dialkoxy-1-oxa-2,6-disilacyclohexanes. Hydrolysis of 1,3-bis(methyl-dichlorosilyl)propane and 1,3-bis(methylalkoxy-chlorosilyl)propane gives a tricyclic carbocyclosiloxane. A study is made of the reactions of 2, 6-dimethyl-2, 6-dialkoxy-1-oxa-2, 6-disilacyclohexane with alcohols, triethylsilanol, triethylchlorosilane, and C₆H₅MgBr.     

Pervaporation of alcohols through highly permeable PIM-1 polymer films

Polycondensation material PIM-1 has attracted the attention of researchers owing to its high transport parameters in gas separation and a high free volume. The pervaporation characteristics of PIM-1 have been systematically studied. Lower aliphatic alcohols (CH₃OH, C₂H₅OH, and n-C₄H₉OH) and water were selected as objects of research. The rates of mass transfer for individual components at various temperatures have been estimated, and for the ethanol-water binary mixture, the process of separation has been examined. The films based on the polymer under study exhibit the properties of organophilic membranes and are characterized by high permeability with respect to alcohols. The apparent activation energy of permeability is low. This behavior is common for pervaporation membranes based on glassy polymers with a high free volume. The parameters of separation for the water-alcohol mixture surpass corresponding values for typical organophilic membranes based on PDMS. These parameters are commensurable with the values observed for membranes based on poly(trimethylsilylpropyne). At the same time, PIM-1 does not demonstrate a rapid decrease in permeability in the course of time.     

Chromatographic properties of poly(1-phenyl-1-propyne)

The chromatographic properties of poly(1-phenyl-1-propyne) (PPP) were studied by separating the C₁–C₁₀ hydrocarbons, alcohols, aromatic, and sulfur-bearing compounds. The influence of the phase percentage for polymer adsorbent (Polysorb-1) on the process of component retention was investigated. A comparison of PPP and the nonpolar liquid phase SE-52 widely used in gas chromatography was performed.     

Production of Mixed Alcohols from Bio-syngas over Mo-based Catalyst

A series of Mo-based catalysts prepared by sol-gel method using citric acid as complexant were successfully applied in the high effcient production of mixed alcohols from bio-syngas, derived from the biomass gasification. The Cu₁Co₁Fe₁Mo₁Zn_0.5-6%K catalyst exhibited a higher activity on the space-time yield of mixed alcohols, compared with the other Mo-based catalysts. The carbon conversion significantly increases with rising temperature below 340 oC, but the alcohol selectivity has an opposite trend. The maximum mixed alcohols yield derived from biomass gasification is 494.8 g/(kg_catal·h) with the C2⁺ (C2-C6 higher alcohols) alcohols of 80.4% under the tested conditions. The alcohol distributions are con-sistent with the Schulz-Flory plots, except methanol. In the alcohols products, the C2⁺ alcohols (higher alcohols) dominate with a weight ratio of 70%-85%. The Mo-based cata-lysts have been characterized by X-ray diffraction and N2 adsorption/desorption. The clean bio-fules of mixed alcohols derived from bio-syngas with higher octane values could be used as transportation fuels or petrol additives.     

Heterocyclic Spiro-naphthalenones. Part II. Synthesis and reactions of some spiro [tetrahydrofuran-2,1′-(2′H-naphthalene)]-2′,5-diones and Spiro [tetrahydrofuran-2,2′-(1′H-naphthalene)]-1′,5-diones

The spiro-lactone 3 was obtained by N-bromosuccinimide (NBS) oxidation of the carboxylate 2 at ? 20°. When 2 was oxidized at 10° the spiro-lactone 4 was the main product. Compound 4 was rearranged with triethylamine to the spiro-lactone 9 whereas the stereoisomeric spiro-lactones 14 and 15 were obtained by NBS oxidation of the carboxylate 13 . The ketones 3, 4, 9, 14 and 15 were reduced with NaBH₄ to the corresponding alcohols 5, 6, 10, 16 and 18 respectively; these were hydrogenated to the alcohols 7, 8, 11 and 20 . The allylic alcohols 5 and 6 gave the benzochromanone 1 when heated in polyphosphoric acid whereas the benzochromanones 12 and 21 were obtained from the alcohols 10 and 16 respectively.     

Structures of 1∶1 inclusion complexes of cholic acid with fluoroethanols; Conformational analysis of fluoroethanols in the host cavity

The crystal structures of the inclusion complexes of cholic acid (CA) with 2-fluoroethanol (MFEtOH), 2,2-difluoroethanol (DFEtOH) and 2,2,2-trifluoroethanol (TFEtOH) have been determined by X-ray crystallography, which demonstrates that the guest alcohols are accommodated inside the cavity provided by CA molecules in a similar manner to that for the ethanol molecule in the CA-ethanol inclusion complex. As distinct from the ethanol molecule, the methylene C atoms of the fluoroethanols are not disordered; instead, the substituted F atoms are statistically disordered. All the alcohols are hydrogen-bonded to the OH groups of CA. The X-ray study showed that 46% of MFEtOH adopt thetrans-trans conformer, which is different from the exclusively predominant conformer in the gas and liquid phases, i.e.,thegauche-trans conformer. The study also showed that the F atoms of DFEtOH are statistically disordered, suggesting the possibility that three conformers exist inside the cavity. Such disorder presumably occurs in order to fill the vacant space around the CH₂F and CHF₂ groups inside the cavity. By contrast, we could not observe any disorder of the F atoms of TFEtOH. Supplementary Data relating to this article are deposited with the British Library as Supplementary Publication No. SUP 82176 (31 pages).     

Synthesis of dialkylaminomethylfurfurals

N, N-Dialkylaminomethylfurfuryl alcohols are synthesized by reacting furfuryl alcohol with dialkylamines in ethanol in the presence of paraformaldehyde. The N, N-dialkylaminomethylfurfurals are obtained by oxidizing the appropriate amino alcohols with active MnO₂.