Reaction #488446

Reaction equation

6-nitroindole

DIEA

t-butyl bromide

→

3-tert-butyl-6-nitro-1H-indole

Yield 22.2%

Solvents

toluene

Conditions

Workup

1. 1
   workup.STIRRINGThe resulting mixture was stirred for 45 min at 120° C
2. 2
   FiltrationThe solid was filtered off
3. 3
   Concentrationthe filtrate was concentrated to dryness
4. 4
   Otherpurified by column chromatography on silica gel (Pet.Ether./EtOAc 20:1)

Procedure

To a mixture of 6-nitroindole (1 g, 6.2 mmol), zinc triflate (2.06 g, 5.7 mmol) and TBAI (1.7 g, 5.16 mmol) in anhydrous toluene (11 mL) was added DIEA (1.47 g, 11.4 mmol) at room temperature under nitrogen. The reaction mixture was stirred for 10 min at 120° C., followed by addition of t-butyl bromide (0.707 g, 5.16 mmol). The resulting mixture was stirred for 45 min at 120° C. The solid was filtered off and the filtrate was concentrated to dryness and purified by column chromatography on silica gel (Pet.Ether./EtOAc 20:1) to give 3-tert-butyl-6-nitro-1H-indole as a yellow solid (0.25 g, 19%). 1H NMR (CDCl3) δ 8.32 (d, J=2.1 Hz, 1H), 8.00 (dd, J=2.1, 14.4 Hz, 1H), 7.85 (d, J=8.7 Hz, 1H), 7.25 (s, 1H), 1.46 (s, 9H).

Source