methyl 6-methyl-1H-indole-5-carboxylate synthesis

Yield:672293-36-6 25%

Reaction Conditions:

with tetrabutyl ammonium fluoride in tetrahydrofuran; for 2 h;Heating / reflux;

Steps:

29.D

To a solution of compound 4-acetylamino-2-methyl-5-trimethylsilanylethynyl-benzoic acid methyl ester (720 mg, 2.37 mmol) in 2 mL THF was added 5 mL of 1M solution of tetrabutylammonium fluoride in THF and refluxed for 2 h. Extracted with EtOAc and washed with water and brine. The organic layer was dried with Na2SO4 and concentrated. The residue was purified by column chromatography using EtOAc and hexane to give 108 mg (25%) of product as white solids. M+H+(190).

References:

US2004/142940,2004,A1 Location in patent:Page/Page column 42-43