反应详情

To a solution of 40 (150 mg, 0.385 mmol) and TEA (107 μl, 0.771 mmol) in anhydrous CH2Cl2 under an atmosphere of nitrogen was added diisobutylamine (67 μL, 0.385 mmol). After stirring for 1 hour, methanol (2 mL) was added followed by iron powder (150 mg) and HCl (conc., 0.4 mL). The reaction mixture was stirred for additional 2 hours and then partitioned between ethyl acetate (20 mL) and a mixture of H2O (20 mL) and NH4OH (2 mL). Organic phase was collected, washed with brine, dried over anhydrous MgSO4, filtered and evaporated. The residue was treated with 2-phenylacetyl isothiocyanate (102 mg, 0.58 mmol) in THF (2 mL), the resultant mixture was allowed to stand for 2 hours at ambient temperature, quenched with methanol (5.0 mL), loaded onto 5 ml of silica gel and purified by flash chromatography using hexane—AcOEt (70:30) as an eluent, to afford title compound 81 (41 mg, 18%) as a white solid 1H NMR (400 MHz, CD3OD) δ (ppm): 8.54 (d, J=5.6 Hz, 1H), 8.08 (dd, J=2.0 and 12.0 Hz, 1H), 7.69 (s, 1H), 7.38-7.49 (m, 2H), 7.28-7.35 (m, 5H), 6.77 (dd, J=1.2 and 5.6 Hz, 1H), 3.77 (s, 2H), 3.46 (bs, 4H), 2.18 (bs, 1H), 2.02 (bs, 1H), 1.02 (bs, 6H), 0.87 (bs, 6H). LRMS (M+1):592.7 (calcd), 593.3 (found).

1. stirringThe reaction mixture was stirred for additional 2 hours
2. custompartitioned between ethyl acetate (20 mL)
3. additiona mixture of H2O (20 mL) and NH4OH (2 mL)
4. customOrganic phase was collected
5. washwashed with brine
6. dry with materialdried over anhydrous MgSO4
7. filtrationfiltered
8. customevaporated
9. waitto stand for 2 hours at ambient temperature
10. customquenched with methanol (5.0 mL)
11. custompurified by flash chromatography