Nitric Acid → 1-(6-Hydroxy-5,5-dimethyl-2-nitro-6,7-dihydro-5H-thieno[3,2-b]pyran-7-yl)piperidin-2-one

Participants

Reaction Steps

The title compound was prepared as described in Example 5 starting with 5,6-dihydro-6-hydroxy-5,5-dimethyl-7-(2-oxopiperidin-1-yl)-7H-thieno[3,2-b]pyran (1.5 g, 5.33 mmol) and 90% nitric acid (2.5 mL) in acetic acid (25 mL) to give the product, 0.837 g (48%), as a yellow solid: mp 210°-211° C.; IR (KBr): 3231, 1613, 1515 and 1492 cm-1 ; MS: m/z 327 (MH+); 1H NMR (CDCl3): δ1.32(s, 3H), 1.51(s, 3H), 1.84(m, 4H), 2.55(m, 2H), 3.20(m, 2H), 3.84(d, J=9.5 Hz, 1H), 4.78(bs, 1H, exchanges with D2O), 5.86(d, J=9.5 Hz, 1H) and 7.40(s, 1H).

Provenance & Evidence