2-Ethyl-2,3-dihydro-5-acetylbenzofuran synthesis

Yield:58741-14-3 150.0 g (79%)

Reaction Conditions:

with hydrogenchloride;AlCl₃ in diethyl ether;acetic anhydride;nitrobenzene;

Steps:

I Synthesis of 2,3-dihydro-2-ethylbenzofuran-5-yl-acetic acid-- (Compound I) according to procedure (1,a)

EXAMPLE I Synthesis of 2,3-dihydro-2-ethylbenzofuran-5-yl-acetic acid-- (Compound I) according to procedure (1,a) A solution of 2,3-dihydro-2-ethylbenzofuran (148.2 g; 1.0 moles) in acetic anhydride (112.3 g; 1.1 moles) was slowly added under stirring to a cold solution of AlCl₃ (266.7 g; 2.0 moles) in nitrobenzene (1100 ml). After stirring overnight at room temperature, the mixture was treated with ice (200 g) and concentrated HCl (200 ml). After steam distillation of the nitrobenzene, the oil residue was taken up in ethyl ether. The solution was washed with water, dried (MgSO₄) and the residue obtained after evaporation of solvent was distilled under reduced pressure yielding 150.0 g (79%) of 2,3-dihydro-2-ethyl-5-acetylbenzofuran as a colorless oil, b.p. 118°-20° C. (0.3 mmHg).

References:

US4029811,1977,A