反应详情

A mixture of ethyl 5-(2-formyl-3-benzyloxyphenoxy)pentanoate (3.61 g, 0.01 M), potassium hydroxide (1.19 g, 0.021 M) and ethanol (40 ml) were stirred at 50°-60° C. for 5 hours. The ethanol was then removed in vacuo, the residue dissolved in water (50 ml) and the solution extracted with ether (2×80 ml). The aqueous layer was then acidified by the addition of 2N aqueous hydrochloric acid and the product extracted with ether (3×50 ml), and the combined extracts washed with water to neutrality, dried, and concentrated in vacuo to give 5-(2-formyl-3-benzyloxyphenoxy) pentanoic acid, 3.0 g, 91% as a yellow oil which crystallised on standing. The crude solid was crystallised from benzene/petroleum spirit 30°-40° C. to give pale cream crystals m.p. 110° C.

1. customThe ethanol was then removed in vacuo
2. dissolutionthe residue dissolved in water (50 ml)
3. extractionthe solution extracted with ether (2×80 ml)
4. additionThe aqueous layer was then acidified by the addition of 2N aqueous hydrochloric acid
5. extractionthe product extracted with ether (3×50 ml)
6. washthe combined extracts washed with water to neutrality
7. customdried
8. concentrationconcentrated in vacuo