Ethyl Acetate → HCID 44230475, compound

Participants

Reaction Conditions

Reaction Steps

A solution of ethyl 4-(tert-butoxycarbonylamino)-3-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzoate (from step 2) (1.0 eq.) and 3-bromopicolino-nitrile (1.0 eq.) in toluene/ethanol (10:1, 0.23 M) was mixed with tetrakis(triphenyl-phosphine)palladium (5 mol %) and anhydrous potassium carbonate (2.0 eq.). The reaction was heated to 100° C. and stirred overnight. After cooling to ambient temperature, the reaction content was diluted with 2% methanol in dichloromethane and water. The two phases were separated, and the aqueous layer was extracted twice with 2% methanol in dichloromethane. The combined organic layers were washed with brine, dried over anhydrous MgSO4, and concentrated en vacuo. The crude material was purified by flash chromatography on a COMBIFLASH® system (ISCO) using 0-40% ethyl acetate in toluene to give a semipure solid, which was then swirled in hot 10% ethyl acetate in hexane, filtered, and dried to give a pure solid. 1H NMR (acetone d-6): δ 9.11 (d, 1H), 9.05 (s, 1H), 8.95 (d, 1H), 8.14 (d, 1H), 7.89-7.92 (dd, 1H), 7.63 (d, 1H), 4.38 (q, 2H), 1.40 (t, 3H). LRMS [M+H]=268.2.

Provenance & Evidence