Ethyl Acetate → 5-Nitro-7-azaindole

Participants

Reaction Steps

5-Nitro-1H-pyrrolo[2,3-b]pyridine 506 of is prepared by reacting 3-methyl-5-nitro-pyridin-2-ylamine 505 with t-butyloxycarbonyl anhydride in an appropriate solvent (e.g. ethyl acetate and hexanes). Concentration and extraction provides a Boc-protected intermediate that is then reacted with 2 equivalents of butyllithium in an appropriate polar solvent (e.g. tetrahydrofuran) with cooling (e.g. 0° C.), followed by the addition of dimethylformamide and stirring for 30 minutes to one hour, followed by addition of 5.5 M HCl. Isolation by conventional means (e.g. extraction and silica gel chromatography) provides 506. (Hands et. al., Synthesis 1996, 877-882.)

Provenance & Evidence