Preparation of phthalimide

phthalimide

Preparation of phthalimide phthalimide: In a three-necked flask fitted with thermometer, gas introduction tube, and wide outlet tube bent downward, 148 grams (1.0 mole) of pure phthalic anhydride is melted and heated to about 170°. At this temperature a rapid stream of ammonia is passed into the molten phthalic anhydride. The ammonia is completely absorbed and steam escapes, carrying with it some phthalic anhydride. Sublimed material which condenses in … Read more

Preparation of phosphorus tribromide

Phosphorus Tribromide

Preparation of phosphorus tribromide phosphorus tribromide: A 500 ml three-necked flask, fitted with a mechanical stirrer, a dropping funnel and a reflux condenser, 28 grams  of pure red phosphorus, and 200 ml of dry carbon tetrachloride (dried over anhydrous calcium chloride) are placed. 198 grams (or 63.5 ml) of dry bromine are placed in the dropping … Read more

Preparation of succinimide

Succinimide

Preparation of succinimide 20 g of succinic acid are dissolved in a small quantity, of water in a basin, and the solution neutralised with ammonia. The solution is boiled to expel excess of ammonia, after which a further 20 g of succinic acid dissolved in water are added. The solution is evaporated to complete dryness on … Read more

Preparation of Pyridinium Tribromide

Pyridinium Tribromide

Preparation of Pyridinium Tribromide Pyridinium Tribromide: To the 1 liter  round bottom flask equipped with a reflux condenser and a dropping funnel 79.1 g of pyridine were placed, and while cooling the flask with ice-water, slowly from a dropping funnel 113 ml of 48% hydrobromic acid was added. Then, the reflux condenser is removed and … Read more

Preparation of Ammonium Chromate

Ammonium Chromate

Preparation of Ammonium Chromate A saturated solution of ammonium chromate is treated with an excess of concentrated ammonium hydroxide solution until the strong smell of ammonia appears and the color of the solution changes from orange to yellow. Then the reaction mixture is cooled in ice water, the obtained yellow crystals of ammonium chromate are filtered, … Read more

Preparation of methyl formate

methyl formate

Preparation of methyl formate Methyl formate is prepared by the action of methyl alcohol saturated with hydrochloric acid on calcium formate. To the round-bottom flask equipped with dropping funnel and a reflux condenser, the latter being connected with a well-cooled descending condenser 100 g of calcium formate are placed. 130 ml methyl alcohol saturated with … Read more

Preparation of 1 4 dimethoxybenzene

1 4 dimethoxybenzene

Preparation of 1 4 dimethoxybenzene 1 4 dimethoxybenzene: The 1 mole of hydroquinone (benzene-1,4-diol, quinol) is treated rapidly with stirring, in a three-necked flask provided with a reflux condenser, stirrer, internal thermometer, and dropping funnel, with 2.5 mole of 10% sodium hydroxide. With vigorous stirring, 2 mole of dimethyl sulfate is added in such a … Read more

Preparation of Phenyl Acetate

phenyl acetate

Preparation of Phenyl Acetate Phenyl Acetate: 15 g of phenol are dissolved in 105 ml (1.6 moles) of 10% aqueous sodium hydroxide solution, and the solution is cooled by adding about 150 g of crushed ice. Then 22 ml (or 24 g) of acetic anhydride is added, the flask is stoppered and is shaken vigorously for … Read more

Preparation of Diphenylmethanol

diphenylmethanol

Preparation of Diphenylmethanol Diphenylmethanol: The reaction flask is attached to a short reflux condenser through which, however, no water flows, instead is filled with methanol. The upper end of the reflux condenser is fitted to a small, water-cooled, descending condenser and a receiver. The reaction flask is charged with 18.2 g of benzophenone and a … Read more