Reaction vessels, stirred

Hydroxyquinoline ( oxine ). The technique adopted in this preparation is based upon the fact that, in general, the reactants glycerol, amine, nitro compound and sulphuric acid can be mixed with temperature control, and then maintained at any convenient temperature below 120° without any appreciable chemical reaction taking place. A pre-mix of the amine, glycerol and sulphuric acid, maintained at a temperature which keeps it fluid (60-90°), is added in portions to a reaction vessel containiug the nitro compound and warmed with stirring to 140-170° at which temperature the Skraup reaction takes place. 

A solution of sodium cyanide [143-33-9] (ca 25%) in water is heated to 65—70°C in a stainless steel reaction vessel. An aqueous solution of sodium chloroacetate [3926-62-3] is then added slowly with stirring. The temperature must not exceed 90°C. Stirring is maintained at this temperature for one hour. Particular care must be taken to ensure that the hydrogen cyanide, which is formed continuously in small amounts, is trapped and neutrali2ed. The solution of sodium cyanoacetate [1071 -36-9] is concentrated by evaporation under vacuum and then transferred to a glass-lined reaction vessel for hydrolysis of the cyano group and esterification. The alcohol and mineral acid (weight ratio 1 2 to 1 3) are introduced in such a manner that the temperature does not rise above 60—80°C. For each mole of ester, ca 1.2 moles of alcohol are added. 

Batch processes for most phenoHc resins employ the equipment shown in Figure 2. Liquid reactants are metered into the stirred reaction vessel through weigh tanks, whereas soHd reactants such as bisphenol A and Ba(OH)2 present handling problems. FaciHties are provided to carry out the reaction under a vacuum or an inert gas. 

Continuous-flow Stirred Tank Reactor (CSTR) A reaction vessel in which the feed is continuously added, and the products continuously removed. The vessel (tank) is continuously stirred to maintain a uniform concentration within the vessel. 

Isolation of the pure a,0 -ieomer, A 250-mL Erlenmeyer flask equipped with a magnetic stirring bar is charged with the isomeric nitriles (20 g, 0.165 mol), prepared in Part A above, and carbon tetrachloride (20 mL). A solution of bromine in carbon tetrachloride (1/9, v/v, ca. 25-30 mL) is added dropwise until the color of excess bromine persists. The reaction vessel is cooled in an ice bath for 30 min, filtered by gravity and the solvent evaporated under reduced pressure. The crude oil is distilled at reduced pressure (bp 40-42 0/0,15 mm) to give a colorless liquid (11-15 g, 55-75%) which is the pure a.p-1somer (Notes 9 and 10). 

The reaction is considerably modified if the so-called emulsion polymerisation technique is used. In this process the reaction mixture contains about 5% soap and a water-soluble initiator system. The monomer, water, initiator, soap and other ingredients are stirred in the reaction vessel. The monomer forms into droplets which are emulsified by some of the soap molecules. Excess soap aggregates into micelles, of about 100 molecules, in which the polar ends of the soap molecules are turned outwards towards the water whilst the non-polar hydrocarbon ends are turned inwards (Figure 2.17). 

A 1-liter three-necked flask equipped with a mechanical stirrer and two dropping funnels is charged with a solution of 42 g (0.176 mole) of sodium periodate in 145 ml of acetone and 180 ml of water. To the stirred solution, camphene (6.7 g, 0.049 mole) is added in small portions. The reaction vessel is then flushed with nitrogen and is main-... 

A setup similar to the preceding one is used in this experiment except that provision should be made for heating the reaction vessel (steam bath, oil bath, or mantle). Lithium aluminum hydride (10 g, 0.26 mole) is dissolved in 200 ml of dry -butyl ether and heated with stirring to 100°. A solution of 9.1 g (0.05 mole) of ra j-9-decalin-carboxylic acid (Chapter 16, Section I) in 100 ml of dry -butyl ether is added dropwise over about 30 minutes. The stirring and heating are continued for 4 days, after which the mixture is cooled and water is slowly added to decompose excess hydride. Dilute hydrochloric acid is added to dissolve the salts, and the ether layer is separated, washed with bicarbonate solution then water, and dried. The solvent is removed by distillation, and the residue is recrystallized from aqueous ethanol, mp 77-78°, yield 80-95 %. 

In a dry, 250 ml, three-necked flask equipped with a dropping funnel and magnetic stirrer are placed 40 ml of dry /-butyl alcohol (distilled from calcium hydride) and 4.0 g (0.036 mole) of potassium /-butoxide. The solution is cooled in ice and 40 g (49 ml, 0.49 mole) of dry cyclohexene is added. Bromoform (10 g, 3.5 ml, 0.039 mole) is added to the cooled, stirred reaction vessel dropwise over about hour, and the vessel is stirred an additional hour with the ice bath removed. The reaction mixture is poured into water (approx. 150 ml), and the layers are separated. The aqueous layer is extracted with 25 mi of pentane, and the extract is combined with the organic layer. The combined layers are dried (sodium sulfate), and the solvent is removed. The product is purified by distillation, bp 10078 mm. 

Camphor Quinone Monotosylhydrazone To 22 g (0.133 mole of camphor quinone in 150 ml of chloroform is added 26.1 g (0.14 mole) of p-toluenesulfonylhydrazide in one batch. The reaction vessel is protected with a drying tube and fitted with a magnetic stirrer, and the mixture is stirred at room temperature for 24 hours. The monotosyl-hydrazone is not isolated. 

To a suspension of 35.2 grams (0.2 mol) of L-cysteine hydrochloride monohydrate stirred in a reaction vessel containing 87 ml of 91% aqueous tetrahydrofuran under a nitrogen... 

To 20 g of the above compound dissolved in 300 ml 95% ethanol In a Parr reaction vessel is added 1.5 g Adams catalyst, platinum dioxide, and the mixture shaken under hydrogen at 50 psi for 1 hour at ambient temperature. The mixture Is then filtered and the ethanol removed on a standard rotary evaporator. The resulting oil is dissolved in 200 ml ether and slowly added to 1,200 ml ether with continuous stirring. The product separates as crystals which are removed after 15 to 30 minutes by filtration. The compound melts at 148°C to 147°C and needs no further purification. 

The 2,3-dichlorophenoxyacetic acid and n-butyryl chloride are placed in the reaction vessel and stirred while the aluminum chloride is added portionwise over a 45-minute period. The mixture then is heated on the steam bath for 3 hours and allowed to cool to room temperature. The gummy product obtained is added to a mixture of 300 ml of crushed ice and 30 ml concentrated hydrochloric acid. The resulting mixture is extracted with ether and the extract evaporated at reduced pressure. The residue Is suspended in boiling water and dissolved by addition of a minimum quantity of 40% sodium hydroxide. After treatment with decolorizing charcoal and filtering, the hot filtrate is made acid to Congo red paper and chilled in ice. 

A mixture of 198 grams of 2,4,5-trichlorophenol and 1B.B grams of paraformaldehyde was heated to 65°C and well stirred. 65 grams of oleum 20% was added dropwise and the addition was So regulated that the temperature increased, without the application of external heat, until it reached 135°C at the end of the acid addition, which took 10 to 15 minutes. The contents of the reaction vessel were stirred for 2 minutes more and then allowed to run into a solution of 100 grams of sodium hydroxide in 1,000 cc of water. 

Chlorine gas was gradually passed into 660 parts of benzene contained in a lead-lined reaction vessel until 890 parts of the gas had been absorbed. The mixture was stirred continuously and the temperature maintained at 15°C to 20°C. 

Into an iron or copper reaction vessel having an efficient stirring device and furnished with a refluxing column and condenser, were charged 330 lb of high quality meta-cresol and 150 lb of glycerol, together with 25 lb of sodium acetate to serve as the catalyst in the reaction. 

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