Their properties are very similar to those of butanes and hexanes.
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Hexanes are commonly used in chromatography as a non-polar solvent. Higher alkanes present as impurities in hexanes have similar retention times as the solvent, meaning that fractions containing hexane will also contain these impurities. In preparative chromatography, concentration of a large volume of hexanes can result in a sample that is appreciably contaminated by alkanes. This may result in a solid compound being obtained as an oil and the alkanes may interfere with analysis.
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The term hexanes refers to a mixture, composed largely (>60%) of hexane, with varying amounts of the isomeric compounds 2-methylpentane and 3-methylpentane, and, possibly, smaller amounts of nonisomeric C5, C6, and C7 (cyclo)alkanes. Hexanes is cheaper than hexane and is often used in large scale operations not requiring a single isomer (e.g., as cleaning solvent or for chromatography).
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The structure is based on two molecules of proguanil, linked with a hexamethylenediamine spacer. Two routes for chlorhexidine synthesis: (1954 to I.C.I.). The compounds designated (...)2 are substituted hexanes.
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This compound is commercially available. It is prepared by exhaustive free radical chlorination of dimethyl carbonate: :CH3OCO2CH3 \+ 6 Cl2 -> CCl3OCO2CCl3 \+ 6 HCl Triphosgene can be easily recrystallized from hot hexanes.
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It has been of great importance in the synthesis of organic compounds. It is soluble in alkanes and often sold as a solution in hexanes. It belongs to the large series of similar compounds such as diethylzinc.
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In industry, hexanes are used in the formulation of glues for shoes, leather products, and roofing. They are also used to extract cooking oils (such as canola oil or soy oil) from seeds, for cleansing and degreasing a variety of items, and in textile manufacturing. They are commonly used in food based soybean oil extraction in the United States, and are potentially present as contaminants in all soy food products in which the technique is used; the lack of regulation by the FDA of this contaminant is a matter of some controversy. A typical laboratory use of hexanes is to extract oil and grease contaminants from water and soil for analysis.
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Hexanes are chiefly obtained by refining crude oil. The exact composition of the fraction depends largely on the source of the oil (crude or reformed) and the constraints of the refining. The industrial product (usually around 50% by weight of the straight-chain isomer) is the fraction boiling at .
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Diethylzinc (C2H5)2Zn, or DEZ, is a highly pyrophoric and reactive organozinc compound consisting of a zinc center bound to two ethyl groups. This colourless liquid is an important reagent in organic chemistry. It is available commercially as a solution in hexanes, heptane, or toluene, or as a pure liquid.
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Phenylboronic acid is soluble in most polar organic solvents and is poorly soluble in hexanes and carbon tetrachloride. This planar compound has idealized C2V molecular symmetry. The boron atom is sp2-hybridized and contains an empty p-orbital. The orthorhombic crystals use hydrogen bonding to form units made up of two molecules.
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It is commercially available as a solution in mixed hexanes, usually at a concentration of about 2 M for laboratory use or 33% for industrial use. As for BuLi, the structure and formula for HxLi are often depicted as a monomer. Like all organolithium compounds, it exists as clusters in solution and as a solid..
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Ground glass joints are translucent when physically free of debris and clean. Solvents, reaction mixtures, and old grease show up as transparent spots. Grease can be removed by wiping with an appropriate solvent; ethers, methylene chloride, ethyl acetate, or hexanes work well for silicone- and hydrocarbon-based greases. Fluoroether-based greases are quite impervious to organic solvents.
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Thermal [6+4] reactions are typically carried out at reflux in a non-polar solvent such as xylene, benzene, or toluene. As higher temperatures may promote lower-order processes, the temperature should be kept as low as possible. Metal-mediated reactions are usually carried out in hexanes, with a small amount of ether for solubility purposes if necessary. Pyrex and uranium glass-filtered light give higher yields than quartz-filtered light.
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Water based pipe coatings, are an environmentally friendly coating that is applied to the inner & outer diameter of ductile iron pipe. They protect against corrosion from the outside and inside, and also protect the product from contamination. The coating is an emulsion manufactured using asphaltene and water primarily, with other raw materials according to the manufacturer's specifications. They came in use in the early 1990s, replacing coatings based on dangerous and environmental harmful solvents, such as benzenes, toluenes, hexanes and other volatile organic compounds.
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Natural gasoline is a liquid hydrocarbon mixture condensed from natural gas, similar to common gasoline (petrol) derived from petroleum. The chemical composition of natural gasoline is mostly five- and six-carbon alkanes (pentanes and hexanes) with smaller amounts of alkanes with longer chains.Sheng Wang, Ying Zhang, Mao-Gang He, Xiong Zheng, and Li-Bin Chen (2014): "Thermal Diffusivity and Speed of Sound of Saturated Pentane from Light Scattering". International Journal of Thermophysics, volume 35, pages 1450–1464. . Quote: "ethane 2.4% w/w, butane 1.3%, pentane 67.1%, hexane 22.0%, heptane 5.7%, and octane 1.5 %".
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Relaying Asymmetry of Transient Atropisomers Structures of BINAP, BINOL, QUINAP Example of use of P,N ligand for asymmetric catalysis In one application the asymmetry in an atropisomer is transferred in a chemical reaction to a new stereocenter. The atropisomer is an iodoaryl compound synthesised starting from (S)-valine and exists as the (M,S) isomer and the (P,S) isomer. The interconversion barrier between the two is 24.3 kcal/mol (101.7 kJ/mol). The (M,S) isomer can be obtained exclusively from this mixture by recrystallisation from hexanes.
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They accomplished this yield by utilizing a cosolvent system of hexanes and methylene chloride, and extrapolated the method to include a number of benzyl halide substrates, as well as alcohols, glucose, and ribose derivatives. This study is one of many where reaction yields in organic synthesis can be optimized by application of polar/non-polar cosolvent systems. Cosolvents also play a role in the biochemical subdiscipline: a 2012 study from researchers at the South China University of Technology reports how cosolvent parameters can be optimized to obtain higher yields in enzyme- catalyzed reactions.Yang, R.L., Li, N., Zong, M.H. Using ionic liquid cosolvents to improve enzymatic synthesis of arylalkyl ß-D-glucopyranosides.
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Soybean oil, meal and beans To produce soybean oil, the soybeans are cracked, adjusted for moisture content, heated to between 60 and 88 °C (140–190 °F), rolled into flakes, and solvent-extracted with hexanes. The oil is then refined, blended for different applications, and sometimes hydrogenated. Soybean oils, both liquid and partially hydrogenated are sold as "vegetable oil," or are ingredients in a wide variety of processed foods. Most of the remaining residue (soybean meal) is used as animal feed. In the 2002–2003 growing season, 30.6 million tons (MT) of soybean oil were produced worldwide, constituting about half of worldwide edible vegetable oil production, and thirty percent of all fats and oils produced, including animal fats and oils derived from tropical plants.
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