L-Lysine → HCID 59770609, compound

Participants

Reaction Steps

5 g (34.2 mmol) of L-lysine are dissolved in 100 ml of water in the presence of 1.4 g (1 eq.) of sodium hydroxide and 8.6 g (3 eq.) of sodium bicarbonate, in a 250 ml three-necked flask equipped with a condenser and a thermometer. A solution of 10.8 ml (3 eq.) of 4-fluoronitrobenzene in 60 ml of ethanol is poured onto the mixture, which is brought to reflux (85°-90° C.) for 5 days. The cooled mixture is extracted with ethyl ether. The aqueous phase is acidified to pH ˜3 with 5 N hydrochloric acid. A gum-like precipitate forms and is extracted with dichloromethane in the presence of a small amount of methanol. The organic phase is washed with water until neutrality is reached, dried over sodium sulphate, and then evaporated to give an orange-coloured oil which crystallizes in the presence of ethyl ether. 11.7 g of a yellow crystalline product are obtained, i.e. an 88% yield.

Provenance & Evidence