Tetrahydro-4H-pyran-4-one → HCID 59016635, compound

Participants

Reaction Steps

3-methoxy-2-methyl-benzoic acid hydrazide (4.14 g, 23 mmol) was suspended in a mixture of 80 mL of ether, 40 mL of CH2Cl2 and 2 drops of acetic acid. A solution of tetrahydro-pyran-4-one (2.3 g, 23 mmol) in 20 mL of CH2Cl2 and 2-3 mL of methanol were added, and the mixture was refluxed for 10 minutes. The reaction mixture was allowed to cool and was concentrated to about 80 mL. Pentane (100 mL) was added, resulting in the formation of a precipitate. The suspension was chilled in a freezer and filtered to yield 5.04 g of 3-methoxy-2-methyl-benzoic acid (tetrahydro-pyran-4-ylidene)-hydrazide as a tan, flocculent, semi-crystalline material. 1H NMR (300 MHz, CDCl3) δ (ppm): 7.2 (t, 1H), 6.98 (d, 1H), 6.95 (d, 1H), 3.9 (t, 2H), 3.86 (s, 3H), 3.8 (t, 2H), 2.65 (t, 2H), 2.42 (t, 2H), 2.35 (s, 3); Rf=0.15 (3:1 ethyl acetate:hexane).

Provenance & Evidence