Methanesulfonyl chloride → 3-(tert-butyloxycarbonyl)-1-chloromethyl-5-nitro-1,2-dihydro-3H-benz[e]indole

Participants

Reaction Conditions

Reaction Steps

A stirred solution of 12 (0.42 g, 1.22 mmol) in pyridine (1.8 mL) was treated dropwise at 0° C. with mesyl chloride (1.13 mL, 1.46 mmol) and then stirred at 20° C. for a further 2 h. The mixture was diluted with water and the resulting solid was collected, dissolved in CH2Cl2, and the solution was washed twice with water, dried (Na2SO4) and evaporated under reduced pressure below 30° C. A mixture of the resulting crude mesylate and LiCl (0.21 g, 5 mmol) in DMF (4 mL) was stirred at 80° C. for 30 min, then cooled and diluted with water. The precipitated solid was dissolved in CH2Cl2 and filtered through a column of silica gel to give a crude product which was triturated with iPr2O/petroleum ether, yielding 3-(tert-butyloxycarbonyl)-1-chloromethyl-5-nitro-1,2-dihydro-3H-benz[e]indole (13) (0.34 g, 77%). A sample recrystallised from iPr2 o/petroleum ether had mp 168-169° C. 1H NMR (CDCl3) δ8.88 (br s, 1 H, H-9), 8.42 (br s, 1 H, H-7), 7.80 (d, J=8.1 Hz, 1 H, H-4), 7.67-7.51 (m, 2 H, H-5,6), 4.34 (br s, 1 H, H-2), 4.20 (t, J=10.2 Hz, 1 H, H-2), 4.17-4.08 (m, 1 H, H-3), 3.92 (dd, J=11.2, 2.5 Hz, 1 H, CHHCl), 3.54 (t, J=10.3 Hz, CHHCl), 1.62 (s, 9 H, C(CH3)3).

Provenance & Evidence