反应详情

To a solution of (R)-ethyl 2-(7-(4-isopropoxy-3-(trifluoromethyl)benzyloxy)-2,3-dihydro-1H-pyrrolo[1,2-a]indol-1-yl)acetate (52.8 g, 111 mmol) in DCM (350 mL) at −5° C. (ice-salt bath) was added a solution of NCS (14.8 g, 111 mmol) in DCM (350 mL) slowly over 20 min via addition funnel. After stirring for 0.5 h the mixture was washed w/sat. aq. sodium thiosulfate (300 mL). The organics were concentrated to about 300 mL and filtered using a column (60 cm×80 cm) containing sodium sulfate (top layer), sand (middle layer), and silica gel (bottom) using DCM as the eluant. The filtrate was concentrated to give (R)-ethyl 2-(9-chloro-7-(4-isopropoxy-3-(trifluoromethyl)benzyloxy)-2,3-dihydro-1H-pyrrolo[1,2-a]indol-1-yl)acetate (54.6 g, 107 mmol, 96% yield) as a white/mildly yellow solid. Exact mass calculated for C26H27ClF3NO4: 509.2, found: LCMS m/z=510.3, [M+H+]; 1H NMR (400 MHz, CDCl3) δ ppm 1.28 (t, J=7.1 Hz, 3 H), 1.37 (d, J=6.1 Hz, 6 H), 2.34 (m, 1 H), 2.52 (dd, J1=16.3, J2=10.2 Hz, 1 H), 2.93 (m, 1 H), 3.22 (dd, J1=16.3, J2=4.0 Hz, 1 H), 3.81 (m, 1 H), 4.00 (m, 1 H), 4.12 (m, 1 H), 4.20 (qd, J1=7.1, J2=1.7 Hz, 2 H), 4.65 (sep, J=6.1 Hz, 1 H), 5.04 (s, 2 H), 6.89 (dd, J1=8.8, J2=2.4 Hz, 1 H), 7.01 (d, J=8.6 Hz, 1 H), 7.06 (d, J=2.4 Hz, 1 H), 7.12 (d, J=8.8 Hz, 1 H), 7.56 (dd, J1=8.5, J2=1.9 Hz, 1 H), 7.67 (d, J=1.9 Hz, 1 H).

1. additionvia addition funnel
2. washwas washed w/sat
3. concentrationThe organics were concentrated to about 300 mL
4. filtrationfiltered
5. additioncontaining sodium sulfate (top layer), sand (middle layer), and silica gel (bottom)
6. concentrationThe filtrate was concentrated