This preview shows page 1. Sign up to view the full content.
Unformatted text preview: 204 PR A C TIC A L ORGANIC C H E M IST R Y R 2 NH + HONO -> R 2 N-NO + H 2 O The nitrosamines are insoluble in water, and the lower members are liquid at ordinary temperatures. The separation of an oily liquid when an aqueous solution of an amine salt is treated with sodium nitrite is therefore strong evidence that the amine is secondary. Diphenylnitrosoamine is selected as a preparation because it is a crystalline substance and is thus easier to manipu- late on a small scale than one of the lower liquid members. For this pre- paration, a fairly pure (and therefore almost colourless) sample of diphenyl- amine should be used. "Technical" diphenylamine, which is almost black in colour, should not be employed. Required: Diphenylamine, i g.; ethanol, 8 ml.; sodium nitrite, 'S g-> hydrochloric acid, 0-8 ml. Prepare two solutions, one containing i g. of diphenylamine in 8 ml. of warm ethanol, and the other containing 0-5 g. of sodium nitrite in i ml. of water, and cool each solution in ice-sodium nitrite in i ml....
View Full Document
- Fall '06
- Organic chemistry