Hydrazine hydrate (1:1) → HCID 89375802, compound

Participants

Reaction Conditions

Reaction Steps

To a stirred 0° C. mixture of ethyl 6-formyl-3,4-dihydro-2H-pyran-5-carboxylate (1.705 g, 9.26 mmol) in methanol (80 mL) was added very quickly 35% hydrazine hydrate (0.311 g, 9.72 mmol). After 20 minutes, the solvent was removed under reduced pressure, and the residue was treated with acetic acid (70 mL) and water (7 mL) and stirred at 110° C. for 20 minutes. The solvents were removed in vacuo. The crude residue was eluted by silica gel chromatography with a 0 to 25% gradient of methanol/dichloromethane to afford the title compound (1.384 g) as a light yellow solid in better than 90% purity. MS (ESI) [m/e, (M+H)+]=153.2. 1H NMR (400 MHz, chloroform-d) δ ppm 10.56 (br s, 1H), 7.53 (s, 1H), 4.17-4.35 (m, 2H), 2.57 (t, J=6.57 Hz, 2H), 1.99-2.08 (m, 2H).

Provenance & Evidence