Benzaldehyde → 2-Benzylidenecyclohexanone

Participants

Reaction Steps

According to the procedure of Birkofer, et al., Chem. Ber., 85, 1495 (1962), a mixture of 1-morpholinyl-1-cyclohexene (125.2 g. 0.75 mole), prepared as described above, benzaldehyde (53.1 g, 0.5 mole), and 200 ml of benzene was refluxed for 12 hours with azeotropic separation of 5.3 ml of water. The reaction mixture was cooled and treated with 300 ml of 6N aqueous hydrochloric acid and stirred at room temperature for one hour. The organic layer was separated, the aqueous layer was extracted with diethyl ether, and the combined organic layer was washed with saturated aqueous sodium chloride solution, dried (MgSO4), and concentrated. Distillation in vacuo (0.07 mm Hg) gave a fraction bp 124°-128° C., 61.1 g of the substitled product (96.2% pure by gas liquid chromatography (GLC) gas analysis). Crystallization from diethyl ether-petroleum ether (30°-60° C.) at -70° C. gave 47.7 g of the subtitled product, mp 48° -50° C. (100% pure by GLC; Birkhofer, et al., loc cit report mp 56° C.

Provenance & Evidence