反应详情

Nitric acid (90%, 1.2 mL, 26.9 mmol) was added to a solution of 5,6- dihydro-6-hydroxy-5,5-dimethyl-7-(2-oxopyrrolidin-1-yl)-7H-thieno[3,2-b]pyran (1.0 g, 3.74 mmol) in acetic acid (30 mL) at 18° C., and stirred at rt for 1.5 h. The resultant solution was poured into ice water (200 mL). Within 10 min a yellow solid crystallized which was collected by filtration, washed with water and triturated in diethyl ether to give the product, 0.487 g (42%), as a yellow solid: mp 214°-217° C.; IR (KBr): 3216, 1655 and 1512 cm-1 ; MS: m/z 313 (MH+); 1H NMR

1. customWithin 10 min a yellow solid crystallized which
2. filtrationwas collected by filtration
3. washwashed with water
4. customtriturated in diethyl ether
5. customto give the product, 0.487 g (42%)