Pyridine → 4-Methylocta-4-ene-1,7-diyne-3-yl alpha-isopropyl-4-chlorophenylacetate

Beteiligte Stoffe

Reaktionsschritte

1.40 Grams (11.4 millimoles) of 4-methylocta-4-ene-1,7-diyne-3-ol is dissolved in 20 ml of a dry benzene, followed by cooling in ice water. Thereafter, 1.80 g (22.8 millimoles) of pyridine is rapidly added thereto at a time and immediately a solution of 2.64 g (11.4 millimoles) of α-isopropyl-4-chlorophenylacetyl chloride in 10 ml of dry benzene is dropwise added thereto for about 30 minutes with stirring. After completion of the addition, stirring is continued for 3 hours at room temperature to complete the reaction. The reaction mixture is poured into 20 g of ice water and the layers are separated. The aqueous layer is extracted with two 10-ml portions of ether. The organic layers obtained is combined and washed once with a 10% hydrochloric acid and three times with water, followed by drying over anhydrous sodium sulfate. After the solvent is removed under reduced pressure, the oily substance obtained is mixed with almost the same amount of pyridine. The mixture is adsorbed to 100 g of silica gel column and purified by developing with a mixed solvent (18 : 1 : 1) of carbon tetrachloride : n-hexane : ether. Thus, 3.19 g of the objective ester is obtained as a pale yellow oily substance (85.1% of theoretical yield). nD23.0 1.5233

Herkunft & Nachweise