Hydrazine → Oxindole

Participants

Reaction Steps

In still a further embodiment, a process is provided for preparing 5-(7-Fluoro-3,3-dimethyl-2-oxo-2,3-dihydro-1H-indol-5-yl)-1-methyl-1H-pyrrole-2-carbonitrile including reacting 7-fluoro-1H-indole-2,3-dione and aqueous hydrazine in ethylene glycol to form the 2-oxindole; alkylating the 2-oxindole at the 3-position; brominating the alkylated 2-oxindole; reacting the brominated 2-oxindole with 5-[1,3,6,2]dioxazaborocan-2-yl-1-methyl-1H-pyrrole-2-carbonitrile, sodium carbonate, and PdCl2(PPh3)2; removing residual PdCl2(PPh3)2 or a by-product thereof using N-acetyl-L-cysteine; and isolating 5-(7-Fluoro-3,3-dimethyl-2-oxo-2,3-dihydro-1H-indol-5-yl)-1-methyl-1H-pyrrole-2-carbonitrile. See, Scheme 6.

Provenance & Evidence