Water → 6-Cyano-5-(1-ethylpiperidin-4-yloxy)-9H-dipyrido[2,3-b:4',3'-d]pyrrole-3-carboxylic acid methyl ester

Participants

Reaction Conditions

Reaction Steps

9-Benzenesulfonyl-3-bromo-5-(1-ethylpiperidin-4-yloxy)-9H-dipyrido[2,3-b;4′,3′-d]pyrrole-6-carbonitrile (150 mg, 0.278 mmol), molybdenum hexacarbonyl (73 mg, 0.278 mmol), Herman's catalyst (trans-di(μ-acetato)bis[(2-di-o-tolylphosphino)benzyl]dipalladium(II), 26 mg, 0.028 mmol) and tri-tert-butylphosphonium tetrafluoroborate (20 mg, 0.069 mmol) were placed in a 5 mL microwave vial. Dioxane (3 mL), methanol (1.5 mL) followed by 1,8-diazabicyclo(5.4.0)undec-7-ene (0.12 mL, 0.833 mmol) were added to the mixture, the tube sealed and heated under microwave irradiation at 150° C. for 15 min. The cooled reaction mixture was diluted with water and extracted into ethyl acetate (4×50 mL). The combined organic phase was washed with brine, dried over sodium sulfate and concentrated in vacuo to afford a residue that was purified by flash chromatography (silica, 12 g column, ISCO, 0-10% MeOH in DCM). The resultant material was triturated with MeOH and collected by filtration to afford the title compound as a pale yellow powder (29 mg, 28%). 1H NMR (CDCl3, 300 MHz): 9.35 (d, J=2.1 Hz, 1H), 9.23 (s, 1H), 8.83 (s, 1H), 5.21-5.06 (m, 1H), 4.05 (s, 3H), 3.07-2.88 (m, 2H), 2.59-2.44 (m, 2H), 2.41-2.06 (m, 6H), 1.20-1.07 (m, 3H). LCMS (Method H): RT=6.56 min, M+H+=380.

Provenance & Evidence