反应详情

1,3-Cyclohexanedione (10 g, 89.2 mmol), 40% aqueous CH3CHO (49.4 g, 445.9 mmol) were dissolved in methanol (40 mL) followed by addition of Hantzsch ester (22.7 g, 89.2 mmol) and pyridine (2.1 g, 18.74 mmol) under nitrogen. The resulting light yellow mixture was stirred at room temperature overnight, then concentrated to give crude product that was re-slurried in a mixture of CH2Cl2 (40 mL) and hexanes (60 mL) to furnish 2-ethyl-1,3-cyclohexanedione (8.6 g, 69%).

1. concentrationconcentrated
2. customto give crude product that