Hexane as solvent

Alkvl Azides from Alkyl Bromides and Sodium Azide General procedure for the synthesis of alkyl azides. In a typical experiment, benzyl bromide (360 mg, 2.1 mmol) in petroleum ether (3 mL) and sodium azide (180 mg, 2.76 mmol) in water (3 mL) are admixed in a round-bottomed flask. To this stirred solution, pillared clay (100 mg) is added and the reaction mixture is refluxed with constant stirring at 90-100 C until all the starting material is consumed, as obsen/ed by thin layer chromatographv using pure hexane as solvent. The reaction is quenched with water and the product extracted into ether. The ether extracts are washed with water and the organic layer dried over sodium sulfate. The removal of solvent under reduced pressure affords the pure alkyl azides as confirmed by the spectral analysis. ... 

Note 2. Commercial butyllithium in hexane as solvent or butyllithium in diethyl... 

Liquid—hquid extraction can be used to obtain high purity linoleic acid from safflower fatty acids or linoleic acid from linseed fatty acids using furfural and hexane as solvents (18). High purity linoleic acid has been obtained from sunflower fatty acids using a dimethylformamide and hexane solvent system (19). 

Table 4. Photolysis constants (k) and Quantum Yields (O) of Brominated Dibenzodioxins and furans in n-Hexane as Solvent. A and B are replicates. 

Figure 4.9) to synthesize isopropyl myristate. This is enabled by a continuous feed of 2-propanol to the reactor, which forms an azeotropic mixture with water. This mixture is distilled, thereby removing the water produced. Afterwards, the immobilized enzyme used can be easily removed by filtration. The feasibility of this technique is also illustrated within the synthesis of glucose stearate. A mixture of ethyl methylketone and hexane as solvent is used, forming an azeotropic mixture with the water produced [42],... 

Conditions 6.20 mmol styrene in benzene, 0.0031 mmol catalyst, 20 bar ( Oi I. (1 1), 60 °C, 12 hours, conversions to aldehydes >99%. b Hexane as solvent.c Lower cross-linking degree. d Higher cross-linking... 

On the basis of the previous work, Polanyi, Skinner and I decided to use hexane as solvent and TiCl4 as catalyst (what we now call initiator). The experimental technique was crude, but its essential feature, retained thereafter, was to use the temperature rise of the reaction mixture, due to the exothermicity of the polymerisations, to measure the rate and the extent (yield Y) of the reactions. 

Pliotolytic. Bussacchini et al. (1985) studied the photolysis (7, = 254 nm) of phenmedipham in ethanol, ethanol/water, and hexane as solvents. In their proposed free radical mechanism, homolysis of the carbon-oxygen bond of the carbamate linkage gave the following photoproducts 3-(hydroxylphenyl)carbamic acid methyl ester, m-toluidine, 2-hydroxy-4-aminomethyl benzoate, 3-hydroxy-5-aminomethyl benzoate, 2-amino-4-hydroxymethyl benzoate, and 2-amino-6-hydroxymethyl benzoate. 

The buzzword polarity, derived from the dielectric approach, is certainly the most popular word concerning solvent effects. (It is the basis for the famous rule of thumb similia similibus solventur, i.e., like dissolves like in English.) We should add like helps like. Let us compare toluene and n-hexane as solvents. At temperatures when both solvents have comparable viscosity, the reaction between 1,2,4,5-tetrafluorobenzene and its anion-radical proceeds in different ways (Werst 1993), depending on the solvent. In toluene, the reaction consists of electron exchange ... 

The automatic procedure for reference spectra generation was first demonstrated for the start-up of a homogeneous catalyzed rhodium hydroformylation of cyclo-octene using Rh4(CO)i2 as precursor, n-hexane as solvent and FTIR as the in situ spectroscopy at 298 K [63]. The first n spectra were (i) empty spectrometer compartment (background), (ii) n-hexane at 0.2 MPa in a high pressure thermostatically controlled cell fitted with Cap2 windows (iii) system equilibrated with 2.0 MPa CO, (iv) system upon addition of cyclo-octene, and (v) system upon addition of Rh4(CO)i2. The n=l reference spectrum, which contained atmospheric... 

Efficient kinetic resolution of chiral unsaturated secondary alcohols by irreversible enzyme-mediated acylation (with vinyl acetate as acylating agent, a crude preparation of Pseudomonas AK, and hexane as solvent) is possible, provided one relatively large and one small substituent are attached to the carbinol carbon. However, the method can be used to resolve substrates that are not amenable to asymmetric epoxidation (see examples 23, 25, 27, 29, where the double bond is either deactivated by an electron-withdrawing substituent, or is of the propargyl alcohol type). Acylation of the / -enantiomer consistently proceeds faster than that of the 5-enantiomer. An example of an allenic alcohol was also reported248. 

Operation of this pilot plant demonstrated that solid/gas biocatalysis was able to compete with classical esterification bioprocesses (systems working with hexane as solvent), reducing any potential risk to a minimum by virtue of the absence of any solvent and greatly simplifying the downstream process by reducing the volumes that have to be treated by distillation to obtain a pure product. 

The main objective of the present work was the production of ethyl esters from the enzymatic alcoholysis of castor oil using n-hexane as solvent. Two commercial lipases, Novozym 435 and Lipozyme IM, were compared. The variables in these experiments were temperature, water and enzyme concentrations in the reaction medium, and the oibethanol molar ratio. An empirical model was built to evaluate the effects of process variables on the conversion, and thus to determine the operating conditions that maximize the production of esters for each enzyme. 

Triplet-triplet absorption by benzene has never been detected and evidence for the presence of triplet benzene in fluids has been obtained only recently using energy transfer measurements. Benzene sensitizes both the fluorescence and the phosphorescence of biacetyl. The concentration dependence of this sensitized luminescence has been shown to be consistent with the presence of triplet benzene in the gas phase43 and in cyclohexane solution,80 though another study using hexane as solvent did not yield any evidence for the presence of triplet benzene,27 presumably because of impurities in the hexane. 

The first domestic crushing of soybean occurred in Seattle, Washington, in 1910, using seed imported from Manchuria.152 Domestically produced soybean was crushed at cottonseed oil mills in the South and linseed (flaxseed) oil mills in the Midwest during the 1910-1920 era.152,156 The first commercially successful domestic soybean solvent continuous extraction plants were installed by Archer Daniels Midland Company (ADM) and the Glidden Company in Chicago in 1934, both using 100 tpd Hildebrandt U-tube extractors and commercial hexane as solvent. They also were equipped to produce phosphatides.153... 

Tris(N-methylanilino)borane has previously been prepared by the reaction of boron trifluoride-ether complexes with three equivalents each of N-methylaniline and a suitable Grignard reagent,1,2 by the reaction of (N-methylanilino)potassium with boron trifluoride-ether complexes,2 and by aminolysis of boron trichloride by N-methylaniline.3 The present general procedure describes a convenient preparation of tris(N-methylanilino)-borane by the reaction of (N-methylanilino)lithium and boron trifluoride-diethyl ether in tetrahydrofuran-hexane as solvent. 

Melt crystallization (MC) fractions, which were prepared according to Traitler et al. [2], were obtained from Sofinol S. A., Manno, CH. Using hexane as solvent two fractions were obtained. Fractionation was performed at -20 °C and the ratio of CB to hexane was 1 5 w/v. 

Remove the hexane on a rotary evaporator to yield crude 2-bromophosphinine. Prepare a column for flash chromatography using silica gel and hexane as solvent, and chromatograph the residue rapidly under a slight nitrogen pressure. 

On the other hand, with hexane as solvent, incorporation of CH2O in the Mn-bonded acyl group is observed ... 

The checkers recommend using toluene or n-hexane as solvents for recrystallization. With these solvents they obtained a yield of 45% of the pure product. 

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