Ammonium Chloride → 7-chloro-4-(2-chloroethoxy)-1H-indole

Participants

Reaction Steps

To a solution of 1-(2-chloroethoxy)-4-chloro-3-nitrobenzene (10.00 g, 0.042 mol) in THF (230 mL) stirred in a cold bath at -50° to -40° C. was added a THF solution of vinylmagnesium bromide (132 mL, 1.0M, 0.132 mol) over 2 minutes. After stirring in the cold bath for 2-2.5 hours, saturated NH4Cl (150 mL) was added to the cold solution and it was removed from the cold bath. 1M HCl was added to dissolve the precipitated solids and the mixture was stirred for 0.5 hour. The layers were separated and the aqueous phase was extracted once with diethyl ether (80 mL). The organic layer combined and dried over anhydrous magnesium sulfate, filtered and the solvent evaporated to give 15.43 g of a dark oil. Purification by chromatography (hexanes-methylene chloride, 2:1) afforded a solid which was triturated with hexane and filtered to afford the product as yellowish white solid: 3.51 g (36%); mp 73°-75° C.; MS EI m/e 229,231, 233 (M+); 1H NMR (400 MHz, DMSO-d6) δ 3.99 (t, 2H;, J=5.1 Hz), 4.34 (t, 2H, J=5.0 Hz), 6.51 (t, 1H, J=2.7 Hz), 6.53 (d, 1H, J=7.8 Hz), 7.04 (d, 1H, J=8.0 Hz), 7.29 (t, 1H, J=2.7 Hz), 11.43 (s, 1H).

Provenance & Evidence