Round bottomed flask with

Fit a 250 ml. round-bottomed flask with a refllix water-condenser down which pieces of sodium may be dropped alternatively, use a flask having a short straight stoppered side-arm for this purpose. 

Fit a 500 ml. round-bottomed flask with a dropping-funnel, and with an efficient reflux water-condenser having a calcium chloride guard-tube at the top. 

Fit a 500 ml. round-bottomed flask with a dropping funnel and a double surface condenser alternatively, the flask may be provided with a two-way addition tube (Fig. II, 13, 9) and the dropping funnel and condenser inserted into the latter. Place 37 g. (46 ml.) of iso-butyl alcohol (b.p. 106-108°) and 40 g. (41 ml.) of pure pyridine in the flask and 119 g. (73 ml.) of redistilled thionyl chloride in the dropping funnel. Insert a cotton wool or calcium chloride guard tube into the mouth of the funnel. Introduce the thionyl chloride during 3-4 hours a white solid... 

Ethyl Bromide. Fit a 1-litre round-bottomed flask with a two holed cork carrying a separatory funnel and a wide (6-8 mm.) bent tube connected to a long efficient condenser set for downward distillation (Fig. 111,35,1) alternatively, Fig. Ill, 35, 1. a two-way addition tube (Fig. 11, 1, 8)... 

Fit a 750 ml. round-bottomed flask with a fractionating column attached to a condenser set for downward distillation. Place 500 g. of diacetone alcohol (the crude product is quite satisfactory), 01 g. of iodine and a few fragments of porous porcelain in the flask. Distil slowly. with a small free flame (best in an air bath) and collect the following fractions (a) 56-80° (acetone and a little mesityl oxide) (6) 80-126° (two layers, water and mesityl oxide) and (c) 126-131° (mesityl oxide). Whilst fraction (c) is distilling, separate the water from fraction (6), dry with anhydrous potassium carbonate or anhydrous magnesium sulphate, and fractionate from a small flask collect the mesityl oxide at 126-131°. The yield is about 400 g. 

Also termed a wide-necked flask or round-bottomed flask with short ring neck (Pyrex). A tliree-necked flask may also be used and the obvious modiflcations made. 

Ayparatue. 2-1 three-necked round-bottomed flask with a dropping funnel, combined with a gas inlet, a mechanical stirrer and a thermometer, combined with a gas outlet. 

Apparatus-. 1-1 three-necked, round-bottomed flask with a thermometer+gas outlet, a stirrer and a gas inlet. During the experiment a slow stream of nitrogen was passed through the flask. A Dewar flask containing liquid nitrogen (note 1) was used as a cooling bath. 

Apparatus 100-ml round-bottomed flask with a stopper, and shaking machine (vibrator), or a lOQ-ml round-bottomed flask with a mechanical stirrer. 

Apparatus. 500-ml round-bottomed, three-necked flask with a gas inlet tube, thermometer and a gas outlet for the preparation of chlorotetrahydropyran 1-1 four--necked, round-bottomed flask with a gas inlet tube, a dropping funnel, a mechanical stirrer and a thermometer, combined with a gas outlet for the preparation of HC=CMgBr and its reaction with chlorotetrahydropyran 1-1 three-necked, round--bottomed flask with a dropping funnel, combined with a gas inlet, a mechanical Stirrer and a thermometer, combined with a gas outlet for the conversion into the allenic alcohol. 

Appavatus-. For the first reaction a 500-ml round-bottomed flask with a thermometer and a gas outlet, connected with a tube filled with calcium chloride for the second reaction a 100-ml round-bottomed flask with a thermometer. 

Apparatus 500-ml flask (see Fig. 1) for the preparation of the sulfinate 250-ml two-necked, round-bottomed flask with a reflux condenser and a thermometer for the 2,3-sigmatropic rearrangement. 

Apparatus 500-ml three-necked, round-bottomed flask with a thermometer, dipping well into the liquid, a 40-cm Widmer column and a dropping funnel the column was connected to a condenser and receiver. 

Apparatus-. 500-ml round-bottomed flask with a combination of thermometer and vent, connected to a drying tube filled with lumps of anhydrous calcium chloride. 

Apparatus 3-1 round-bottomed flask with a wide neck. 

The reaction mixture is then transferred to a 2-I. round-bottom flask with wide neck, and to this is added all at once 300 g. of cracked ice, and the mixture is rapidly agitated by a rotary motion until the decomposition is complete (Note 7). Sufficient 30 per cent sulfuric acid is added to dissolve the magnesium hydroxide, and the mixture is then steam-distilled until oil no longer collects on the surface of the distillate. The distillate, which amounts to 1500-2500 cc., is saturated with sodium chloride and the upper layer separated. The aqueous layer is extracted with two loo-cc. portions of ether and the ether extract added to the alcohol layer. The ether solution is dried over anhydrous potassium carbonate, filtered, and heated carefully on the steam cone until all the ether is distilled. The crude alcohol is warmed one-half hour with about 5 g. of freshly dehydrated lime (Note 8). After filtering again and washing the lime with a little ether, the ether is distilled and the alcohol is distilled in vacuo from a Claisen flask (Note g). The carbinol distils at 88-93 /18 mm. (practically all distilling at 91°). The yield is 70-74 g. (61-65 P r cent of the theoretical amount) (Note 10). 

Tetrabutylammonium fluoride trihydrate (Aldnch) is heated in a round-bottom flask with magnetic stirring at 40-45 C under vacuum (<0.1 mm of Hg) After several hours, the sample liquefies. Heating is continued until the sample loses 20% of its original weight (usually ca 48 h). The resulting anhydrous TBAF (singlet at -99 ppm, F NMR) contains 0 1-03 molar equivalent of water (by NMR) and ca 10% tetrabutylammonium bifluoride (a doublet at -146 ppm, (J = 123 Hz, F NMR) This oil must be used immediately. 

The carbonyl compound to be reduced (0.1 mole) is placed in a 250-ml round-bottom flask with 13.5 g of potassium hydroxide, 10 ml of 85% hydrazine hydrate, and 1(X) ml of diethylene glycol. A reflux condenser is attached and the mixture is heated to reflux for I hour (mantle). After refluxing 1 hour, the condenser is removed and a thermometer is immersed in the reaction mixture while slow boiling is continued to remove water. When the pot temperature has reached 200°, the condenser is replaced and refluxing is continued for an additional 3 hours. The mixture is then cooled, acidified with concentrated hydrochloric acid, and extracted with benzene. The benzene solution is dried, and the benzene is evaporated to afford the crude product, which is purified by recrystallization or distillation. 

The ketoester is mixed in a suitable round-bottom flask with excess 6 N sulfuric acid. The flask is fitted with a condenser and a mantle, and the mixture is refluxed gently for 3-4 days. The cooled reaction mixture is extracted with ether, the ether is washed with bicarbonate solution and water, then dried, and the solvent is evaporated. On distillation, the residue affords 2-methylcyclooctanone, bp 97-98718 mm, 86712 mm, 1 4656,... 

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