Methyl chloroformate → 5-(3,6-dihydro-4-hydroxy-6-oxo-2-phenyl-2H-pyran-2-yl)pentanoic acid amide

Participants

Reaction Conditions

Reaction Steps

To a 50 mL reaction flask was added 1.2 mmol of 5-(3,6-dihydro-4-hydroxy-6-oxo-2-phenyl-2H-pyran-2-yl)pentanoic acid (±), 2.4 mmol of 4-methylmorpholine, and 10 mL of CH2Cl2. The reaction was cooled to 0° C. and 2.4 mmol of methyl chloroformate in 3 mL of CH2Cl2 was added. The reaction was stirred at 0° C. for 2 hours. Ammonia was bubbled into the vessel for 10-15 minutes and the reaction allowed to stir for 30 minutes at 0° C. The reaction was poured into ethyl acetate and 1N HCl, the aqueous layer extracted with ethyl acetate, dried over MgSO4, and concentrated. The crude solid was triturated using CH2Cl2 to afford 5-(3,6-dihydro-4-hydroxy-6-oxo-2-phenyl-2H-pyran-2-yl)pentanoic acid amide (±) as a solid (m.p. 173°-174° C.). 1H NMR (DMSO-d6) δ0.8-1.0 (m, 1H), 1.1-1.3 (m, 1H), 1.3-1.5 (m, 2H), 1.8-2.0 (m, 4H), 2.9 (ABq, 2H), 4.8 (s, 1H), 6.6 (s, 1H), 7.2 (s, 1H), 7.2-7.5 (m, 5H), 11.4 (s, 1H).

Provenance & Evidence