Hydrochloric Acid → 3-Hydroxy-5-(benzo[b]thien-5-yl)cyclohex-2-en-1-one

Beteiligte Stoffe

Reaktionsschritte

Diethyl malonate (7.16 g) was added to a solution of sodium metal (1 equiv) in anhydrous absolute ethanol (40 ml). 1-(Benzo[b]thien-5-yl)but-1-en-3-one (8.7 g) was added to the solution and the mixture was heated under reflux for 2 hr. An aqueous solution of potassium hydroxide (5.3 g in 50 ml water) was added and the mixture was heated under reflux for a further 5 hr. The hot mixture was acidified by dropwise addition of a dilute aqueous hydrochloric acid solution. After cooling, the product was filtered off and dried by azeotropic distillation with toluene to give 3-hydroxy-5-(benzo[b]thien-5-yl)cyclohex-2-en-1-one as a yellow solid, mp 192° C.

Herkunft & Nachweise