反应详情

A mixture of 9.0 g (40.5 mmoles) of 2,6-dihydroxy-2,5,7,8-tetramethylchroman and 4.54 g (69 mmoles) of 85% KOH in 61 ml of acetonitrile was rapidly stirred and refluxed for 4 hr. The dark-colored mixture, which consisted of two phases, was cooled in an ice bath and treated dropwise, with stirring, with 25 ml of 3 N aqueous HCl whereupon the reaction mixture became lighter in color. This mixture was poured into 1 N aqueous HCl and worked-up with ethyl acetate in the usual manner (the organic extracts were additionally washed with saturated aqueous NaHCO3 solution) affording 14.8 g of rac.-3,4-dihydro-6-hydroxy-2,5,7,8-tetramethyl-2H-1-benzopyran-2-acetonitrile as a red solid.

1. temperaturerefluxed for 4 hr
2. temperaturewas cooled in an ice bath
3. additiontreated dropwise
4. washwere additionally washed with saturated aqueous NaHCO3 solution)