反应详情

The product from Stage 3 (0.44 g) was dissolved in dry dichloromethane (10 ml) with stirring and oxalyl chloride (0.212 g) was added. When no further gas was evolved the mixture was evaporated under reduced pressure to give a pale yellow oil which contained 2-(3,5-dichlorophenyl)-3-methoxypropionic acid chloride. The acid chloride was dissolved in dry dichloromethane (5 ml) and 4-amino-4-methylpent-2-yne hydrochloride (prepared as described below; 0.222 g) was added. The suspension was stirred at ambient temperature whilst triethylamine (0.48 ml) was added dropwise. The mixture was stirred for 3 hours, diluted with water, acidified with dilute aqueous hydrochloric acid (2M) then extracted with further dichloromethane. The organic extract was separated, washed with brine then dried over magnesium sulphate and evaporated under reduced pressure to give a gum. The gum was fractionated by chromatography (silica; hexane:ethyl acetate, 3:1 by volume) to give the required product as a colourless solid, 0.28 g, mp 107-110° C.

1. customwas evaporated under reduced pressure
2. customto give a pale yellow oil which
3. additionwas added dropwise
4. stirringThe mixture was stirred for 3 hours
5. extractionthen extracted with further dichloromethane
6. extractionThe organic extract
7. customwas separated
8. washwashed with brine
9. dry with materialthen dried over magnesium sulphate
10. customevaporated under reduced pressure
11. customto give a gum