反应详情

温度

90 °C

61.1 mg 3 was dissolved in 1 ml DMF, to which was added 60 μl tert-butyl bromoacetate followed by 0.4 ml DBU solution (1M in NMP) and catalytic amount of KI. The mixture was heated with microwave initiator (biotage) to 90° C. and reacted for 20 min. TLC indicated the reaction didn't go complete. Additional 13.5 eq. of tert-butyl bromoacetate was added. The mixture was continued at 90° C. for 30 min. The mixture was diluted with ethyl acetate to 40 ml and washed with 0.5 M NaHSO4, H2O and brine. Dried over Na2SO4, the organic phase was concentrated and the residue was purified via flash chromatography (5 g silica gel, Hex/EtOAc) affording 43 mg (51.3%) solid. 1H NMR (400 MHz, CDCl3) δ 7.85 (d, J=7.8 Hz, 1H), 7.80 (dd, J=8.1, 1.2 Hz, 1H), 7.61 (dd, J=5.0, 1.3 Hz, 1H), 7.56 (dd, J=3.8, 1.3 Hz, 1H), 7.46-7.36 (m, 2H), 7.16 (d, J=8.4 Hz, 1H), 6.99 (dd, J=5.0, 3.8 Hz, 1H), 6.31 (d, J=8.4 Hz, 1H), 3.92 (s, 2H), 1.52 (s, 9H).; LRMS (ES+) 420 (M+H)+; HRMS (ES+) m/z calculated for C20H22NO5S2 (M+H)+ 420.0934, found 420.0932.

1. customreacted for 20 min
2. customthe reaction didn't go complete
3. washwashed with 0.5 M NaHSO4, H2O and brine
4. dry with materialDried over Na2SO4
5. concentrationthe organic phase was concentrated
6. customthe residue was purified via flash chromatography (5 g silica gel, Hex/EtOAc)