反应详情

To a stirred solution of 3 (110.9 g, 324.8 mmol, 1 equiv.) in 2:1 ethanol/methanol (650 mL in total, 0.5 M) was added anhydrous hydrazine (30.6 mL, 974.5 mmol, 3 equiv.). The reaction was refluxed for 16 h monitoring by TLC (1:1 MeOH/EtOAc). The reaction mixture was concentrated in vacuo. The residue was dissolved in CH2Cl2 and washed with water (100 mL) and brine (100 mL). The aqueous layer was extracted with CH2Cl2 (3×80 mL) and EtOAc (80 mL). The combined organic layer was dried over Na2SO4, filtered and concentrated in vacuo. Purification with recrystallization in methanol gave 4 (96.3 g, 91%) as white solid. On the milligram-scale, the reaction was run in ethanol (0.06 M). 1H NMR (500 MHz, CD3OD): δ 7.85 (d, J=8.2 Hz, 2H), 7.51 (d, J=8.2 Hz, 2H), 3.61 (s, 2H), 3.04 (s, 2H), 2.54 (broad s, 8H). 13C NMR (126 MHz, CD3OD): δ 170.2, 142.8, 142.4, 129.7, 126.0, 61.9, 59.8, 53.0, 52.6. HRMS (ESI). found: 328.1436 (M+1). calcd for C13H22N5O3S: 328.1443. m.p.: 194.5-196.0. IR (neat): 3320, 1670, 1158 cm−1.

1. concentrationThe reaction mixture was concentrated in vacuo
2. dissolutionThe residue was dissolved in CH2Cl2
3. washwashed with water (100 mL) and brine (100 mL)
4. extractionThe aqueous layer was extracted with CH2Cl2 (3×80 mL) and EtOAc (80 mL)
5. dry with materialThe combined organic layer was dried over Na2SO4
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customPurification
9. customwith recrystallization in methanol