Sodium Carbonate → Ethyl 5-amino-8-methylbenzo[f][1,7]naphthyridine-2-carboxylate

Participants

Reaction Steps

A solution of tert-butyl 5-methyl-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenylcarbamate (from Example 5/step 2) (1.0 eq.) and ethyl 5-chloro-6-cyanonicotinate (from the previous step) (1.0 eq.), tetrakis(triphenyl-phosphine)palladium (5 mol %), and 2N aqueous sodium carbonate solution (2.0 eq.) in toluene/ethanol (2:1, 0.03 M) was stirred at 100° C. overnight. After cooling to ambient temperature, the reaction content was diluted with methanol. The insoluble solids were filtered off, and the filtrate was concentrated en vaccuo to obtain a crude residue. The crude material was purified by flash chromatography on a COMBIFLASH® system (ISCO) using 0-80% ethyl acetate in hexane to give ethyl 5-amino-8-methylbenzo[f][1,7]naphthyridine-2-carboxylate.

Provenance & Evidence