Pyridine → 5-(1-Hydroxypropylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione

Participants

Reaction Conditions

Reaction Steps

To a solution of 2,2-dimethyl-1,3-dioxane-4,6-dione (4.41 g, 30.0 mmol) and pyridine (4.85 mL, 60.0 mmol) in dichloromethane (24 mL) at 0° C. under argon is added propionyl chloride (2.95 mL, 33.0 mmol). The mixture is stirred at 0° C. for 1 h and at room temperature for 1 h before being diluted with 2 N HCl (40 mL) and extracted with dichloromethane (80 mL). The extract is washed (brine) and dried. Solvent is removed at reduced pressure to give 5.57 g (93%) of 2 as a yellow solid, mp 43-46° C. IR 3345, 2856, 1715, 1456 cm−1; 1H NMR (CDCl3) δ 1.29 (t, J=7.5 Hz, 3H, CH2CH3), 1.76 (s, 6H, CH3, CH3), 3.14 (q, J=7.5 Hz, 2H, CH2CH3), 15.42 (bs, 1H, OH).

Provenance & Evidence