Stirrers rotary

Metallic Na and a dispersing medium are heated at 200-220°C with brisk stirring, using an autoclave provided with a magnetic stirrer (rotary and rocking autoclaves are less suitable). At the same time, electrolytic Hg is forced in from a steel cylinder or with a compressor. Hydrogenation takes place at all pressures. The higher pressure level is important only insofar as it determines the rate of H3 uptake. 

Sticky when wet difficult-to-fluidize Vibrated bed Well-mixed fluid bed or with stirrers Rotary dryer Backmixed feed (solids backmixing)... 

A 600-mL, three-necked, round-bottomed flask 1s equipped with a mechanical stirrer, a short gas inlet tube, and an efficient reflux condenser fitted with a potassium hydroxide drying tube. The flask is charged with 13.4 g (0.05 mol) of 3-ben2y1-5-(2-hydroxyethyl)-4-methyl-l,3-th1azol1um chloride (Note 11, 72.1 g (1.0 mol) of butyraldehyde (Note 2). 30.3 g (0.3 mol) of triethylamine (Note 2), and 300 raL of absolute ethanol. A slow stream of nitrogen (Note 3) is begun, and the mixture is stirred and heated In an oil bath at 80°C. After 1.5 hr the reaction mixture is cooled to room temperature and concentrated by rotary evaporation. The residual yellow liquid Is poured Into 500 mL of water contained 1n a separatory funnel, and the flask is rinsed with 150 mL of dichloromethane which is then used to extract the aqueous mixture. The aqueous layer is extracted with a second 150-mL portion of... 

C. Thiete 1,1-dioxide. A sample of 3-chlorothietane l,l-d1ox1de (8.0 g, 0.057 mol) Is dissolved In dry toluene (300 ml) (Note 7) In a 500-mL, twonecked, round-bottomed flask equipped with a reflux condenser, magnetic stirrer, heating mantle (or silicone oil bath), and thermometer. The reaction Is heated to 60° C and tri ethyl amine (28.7 g, 0.28 mol, 39,5 ml) Is added through the condenser. The reaction mixture Is stirred for 4 hr and triethyl-amine hydrochloride is removed by filtration and washed with toluene (100 mL), Toluene is removed on a rotary evaporator and the residue is recrystallized from diethyl ether-ethanol (Note 8) to give a white solid (4.5-4.8 g, 75-81 ) mp 49-50°C (llt mp 52-54°C). 

B. Di-tert-butyl dicarbonate. A solution of 20.0 g. (0.076 mole) of di-i-butyl tricarbonate in 75 ml. of carbon tetrachloride is placed in a 600-ml. beaker fitted with a magnetic stirrer, and 0.10 g. (0.0009 mole) of freshly sublimed l,4-diazabicyclo[2.2.2]octane (DABCO) is added (Note 9). Rapid evolution of carbon dioxide begins at once. The reaction mixture is stirred at 25° for 45 minutes to complete the loss of carbon dioxide (Note 10), and then 35 ml. of water, containing sufficient citric acid to make the aqueous layer slightly acidic, is added. The layers are separated and the organic layer is dried over anhydrous magnesium sulfate and then concentrated at 25° with a rotary evaporator. The residual liquid is distilled under reduced pressure to separate 13.3-15.1 g. (80-91%) of di-butyl dicarbonate as a colorless liquid, b.p. 55-56° (0.15 mm.) or 62-65° (0.4 mm.) n T> 1.4071-1.4072 (Note 11). 

B. (l-Azido-3,3-dimethoxy-l-propenyl)benzene. In a 2-1., one-necked, round-bottomed flask equipped with a magnetic stirrer and powder funnel are placed 156 g. (0.45 mole) of the iodoazide from Part A and 1500 ml. of anhydrous ether. The solution is stirred and cooled in an ice-salt bath (— 5° to 0°), and 62 g. (0.55 mole) of potassium <-butoxide (Note 6) is added. The powder funnel is then replaced by a calcium chloride drying tube and the mixture is stirred for 4 5 hours at 0°. At the end of this time 350 ml. of water is added while the mixture is still cold. The ethereal layer is then separated and washed with three 350-ml. portions of water and dried over magnesium sulfate. The solvent is removed with a rotary evaporator without heating, leaving 67-75 g. (68-76%) of (l-azido-3,3-dimethoxy-l-propenyl)-benzene as a dark oily liquid (Note 7). This material can be used without further purification for Part C (Note 8). 

In a 500-ml three-necked flask equipped with a mechanical stirrer, a condenser, and a dropping funnel (drying tubes) is placed a solution of 15.1 g (0.01 mole) of 1-pyrrolo-dino-1-cyclohexene in 100 ml of dry dioxane. The solution is cooled to 0-5° in an ice bath, and acrolein (5.9 g, 0.0105 mole) is added with stirring over 20 minutes. The solution is then allowed to stir at room temperature overnight. Dioxane and excess acrolein are removed (rotary evaporator) and the residue is distilled at reduced pressure to give the product, bp 125-12770.5 mm, yield 75%. 

B. 2-Acetyl-6,l-dimethoxy-l-methylene-l,2,3,4-tetrahydroisoquinoline [Isoquinoline, 2-acetyl-l,2, A,4-tetrahydro-6,7-dimethoxy-l-methylene-]. A 1-1., three-necked, round-bottomed flask equipped with a mechanical stirrer, a reflux condenser topped with a calcium chloride drying tube, and a thermometer is charged with 110 ml. of acetic anhydride, 110 ml. of pyridine, and 45.0 g. (0.22 mole) of the dihydroisoquinoline prepared in Part A. The reaction mixture is stirred and heated at 90-95° for 30 minutes, stored at room temperature overnight, and concentrated by distillation at 50° using a rotary evaporator. The residue is diluted with 20 ml. of ethyl acetate, and another evaporation under reduced pressure gives material that can be crystallized from 75 ml. of ethyl acetate to yield 38.5 41.0 g. (72-77%) of product, m.p. 106-107° (Note 11). 

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