Heptane-, sodium

Most microemulsions are made with four components. In this case, Eq. 2.20 cannot be used, unless a pseudo-component is defined, such as a given ratio of surfactant to alcoholic cosurfactant. This active mixture is considered as the third component and is placed at the C apex. Figure 2.16 shows the phase diagram of the ternary system water/heptane/sodium bis (2-ethylhexyl) sulfosuccinate (Aerosol OT or AOT) [35]. AOT is an anionic surfactant able to form W/0 microemulsions without the need of a cosurfactant. Figure 2.17 shows the phase diagram of the pseudo-ternary system water/heptane/(CTAB + w-butanol) [31]. CTAB is a cationic surfactant that needs to be associated with a cosur ctant to form microemulsions. The ratio CTAB/butanol was constant (1/1 w/w) for all compositions represented in the phase diagram. The hatched areas corres-... 

AI2O3, CS2, EDTA, acetone, heptane, sodium carbonate, tetrahydrofuran, ethyl acetate, isopropanol Formaldehyde, toluene diisocyanate,... 

Penta(ethylene glycol) monododecyl ether carbon dioxide and n-heptane/sodium bis(ethylhexyl)snlfosnccinate 2009HOL... 

Alkali Metal Catalysts. The polymerization of isoprene with sodium metal was reported in 1911 (49,50). In hydrocarbon solvent or bulk, the polymerization of isoprene with alkaU metals occurs heterogeneously, whereas in highly polar solvents the polymerization is homogeneous (51—53). Of the alkah metals, only lithium in bulk or hydrocarbon solvent gives over 90% cis-1,4 microstmcture. Sodium or potassium metals in / -heptane give no cis-1,4 microstmcture, and 48—58 mol % /ram-1,4, 35—42% 3,4, and 7—10% 1,2 microstmcture (46). Alkali metals in benzene or tetrahydrofuran with crown ethers form solutions that readily polymerize isoprene however, the 1,4 content of the polyisoprene is low (54). For example, the polyisoprene formed with sodium metal and dicyclohexyl-18-crown-6 (crown ether) in benzene at 10°C contains 32% 1,4-, 44% 3,4-, and 24% 1,2-isoprene units (54). 

Estrone methyl ether (100 g, 0.35 mole) is mixed with 100 ml of absolute ethanol, 100 ml of benzene and 200 ml of triethyl orthoformate. Concentrated sulfuric acid (1.55 ml) is added and the mixture is stirred at room temperature for 2 hr. The mixture is then made alkaline by the addition of excess tetra-methylguanidine (ca. 4 ml) and the organic solvents are removed. The residue is dissolved in heptane and the solution is filtered through Celite to prevent emulsions in the following extraction. The solution is then washed threetimes with 500 ml of 10 % sodium hydroxide solution in methanol to remove excess triethyl orthoformate, which would interfere with the Birch reduction solvent system. The heptane solution is dried over sodium sulfate and the solvent is removed. The residue is satisfactory for the Birch reduction step. Infrared analysis shows that the material contains 1.3-1.5% of estrone methyl ether. The pure ketal may be obtained by crystallization from anhydrous ethanol, mp 99-100°. Acidification of the methanolic sodium hydroxide washes affords 10-12 g of recovered estrone methyl ether. 

Nucleophilic addition to car bonyl groups sometimes leads to a mixture of stereoisomeric products. The direction of attack is often controlled by steiic factors, with the nucleophile approaching the carbonyl group at its less hindered face. Sodium borohydride reduction of 7,7-dirnethylbicyclo[2.2.1]heptan-2-one illustrates this point ... 

FinkelStein reaction with sodium iodide is followed by acylation of heptane-3,5-dione to complete the synthesis of arildone (55). ... 

The chloroform layer is washed with a dilute aqueous sodium hydroxide solution, thereafter with water, and is finally dried over potassium carbonate. The residue, which is obtained after evaporation of the chloroform, is dissolved by heating in a mixture of 25% of toluene and 75% of heptane. On cooling this solution to about 20°C the product precipitates. That compound is reduced with LiAIH4 to give cinnarizine. 

Chemical Name 6-[3-(2,6-dich orophenyl)-5-methyl-4-isoxazolecarboxamido] -S.G-dimethyl-7-oxo-4-thia-1-azabicyclo[3.2.0] heptane-2-carboxylic acid sodium salt... 

With stirring, 44.1 g of isobutyric acid is added to a mixture of 51.0 g of diisopropylamine, 23.2 g of a 57% sodium hydride dispersion in mineral oil, and 350 ml of tetrahydrofuran. When gas evolution subsides, the mixture is heated at reflux for 15 minutes, cooled to 0°C, and treated with 345 ml of a 1.45M solution of n-butyllithium in heptane. After 5 hr, the... 

A mixture of 42.5 grams (0.17 mol) of methyl a-cyclopentyl mandelate and 18 grams (0.175 mol) of 1-methyl-3-pyrrolidinol in 500 ml of heptane was refluxed under a Dean Stark moisture trap, with the addition of four 0.1 gram pieces of sodium at 1-hour intervals. After 5 hours refluxing the solution was concentrated to one-half volume, and extracted with cold 3N HCI. The acid extract was made alkaline with aqueous sodium hydroxide and extracted with ether which was washed, dried over sodium sulfate, filtered and concentrated. The residue was fractionated at reduced pressure. Yield 33 grams (64%) ... 

Thermal stabilization of polyolefins has been first demonstrated for low-molecular models-normal structure alkanes [29]. It has been shown that metallic sodium and potassium hydroxide with absorbent birch carbon (ABC) as a carrier are efficient retardants of thermal destruction of n-heptane during a contact time of 12-15 s up to the temperature of 800°C [130]. Olefins and nitrous protoxide, previously reported as inhibitors of the hydrocarbon thermal destruction, are ineffective in this conditions. 

Metallic sodium practically completely retards crecking of heptane and hexadecane over a period of 120 min at 500°C, and in presence of potassium hydroxide with ABC carrier a fraction of decomposed hydrocarbon amounts to 2.1% in case of heptane and to 3.1% for hexadecane. 

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