Sodium Carbonate → methyl 3-(1-methylethyl)-7-nitro-1H-indole-5-carboxylate

Beteiligte Stoffe

Reaktionsschritte

To a solution of ethyl 3-bromo-4-[(3-methyl-2-buten-1-yl)(trifluoroacetyl)amino]-5-nitrobenzoate (D215) (12.9 g, 28.5 mmol, 1 equiv) in DMF (130 ml) were added HCOONa (1.94 g, 28.5 mmol, 1 equiv), Na2CO3 (7.54 g, 71.2 mmol, 2.5 equiv), Bu4NCI (8.7 g, 31.3 mmol, 1.1 equiv) and palladium (II) acetate (320 mg, 1.42 mmol, 0.05 equiv) and the resulting mixture was stirred under nitrogen for 1 h then cooled to room temperature and concentrated in vacuo. The residue was partitioned between AcOEt and H2O and the two layers were separated. The insoluble material in the aqueous phase was filtered off through a pad of celite and the aqueous layer extracted twice with AcOEt. The combined organic layers were washed with brine, dried over MgSO4 and concentrated in vacuo to give methyl 3-(1-methylethyl)-7-nitro-1H-indole-5-carboxylate (D218) (10.1 g, 128%) as a black solid which was used in the next step without further purification.

Herkunft & Nachweise