CAUTION: All operations should be conducted behind a safety screen.
- In the course of 15 minutes t-butylamine (1,1-dimethylethylamine, 100g) is added to a stirred solution of potassium permanganate (650g) in 3 litres of water; the temperature rises to 45 °C.
- The stirring is continued for 8 hours without external heating, and the solution is then held at 55 ± 5 °C for a further 8 hours.
- The product is isolated by steam distillation and washed with dilute hydrochloric acid, then with water and dried.
- Distillation gives 117g (83%) of the tertiary nitro compound, b.p. 127-128 °C, nᴅ²⁸ 1.3980, m.p. 25-26 °C.
Cognate preparation: General procedure for the oxidation of primary and secondary amines using m-chloroperbenzoic acid
- m-Chloroperbenzoic acid (4.1g, 0.020 mol, 85% pure) is dissolved in 30 ml of 1,2-dichoroethane in a three-necked flask equipped with a condenser and a pressure-equalising dropping funnel.
- The amine (0.0050 mol) in 3-5 ml of solvent is added dropwise to the refluxing peracid solution.
- Refluxing temperature 83 °C, time 3 hours.
- After the addition the reaction mixture is cooled, filtered and washed with three 50-ml portions of 1 𝗠 sodium hydroxide solution and dried over magnesium sulphate.
- Removal of solvent gives a product which is distilled or recrystallised as appropriate.
- The following amines have been oxidised by this procedure: cyclohexylamine, 2-aminobutane, hexylamine, propylamine and 2-phenyl-l-aminoethane.
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