Cesium carbonate → (S)-3-[6-(5-cyano-6-methoxy-pyridin-3-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-ylamino]-pyrrolidine-1-carboxylic acid tert-butyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a glass vial was added (S)-3-(5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-ylamino)-pyrrolidine-1-carboxylic acid tert-butyl ester (intermediate 23) (566 mg, 1.77 mmol), 5-bromo-2-methoxynicotinonitrile (453 mg, 2.13 mmol), cesium carbonate (1155 mg, 3.54 mmol), tris(dibenzylideneacetone)dipalladium(0) (162 mg, 0.18 mmol), X-Phos (287 mg, 0.60 mmol) and anhydrous tert-butanol (5 mL). The vial was flushed with a stream of argon for 15 sec and capped. The mixture was heated with stirring for 18 h at 110° C. Allowed to cool and partitioned between CH2Cl2 (20 mL) and water (10 mL) and filtered the biphasic mixture through a celite pad. The organic layer was separated by filtering through a phase separation tube and concentrated in vacuo. Purified by flash column chromatography on silica gel with heptane/EtOAc, 100/0 to 0/100 then EtOAc/MeOH (90/10) to give (S)-3-[6-(5-cyano-6-methoxy-pyridin-3-yl)-5,6,7,8-tetrahydro-pyrido[4,3-d]pyrimidin-4-ylamino]-pyrrolidine-1-carboxylic acid tert-butyl ester as a brown gum (234 mg, 29% yield). LCMS: [M+H]+=452.1, Rt(4)=0.90 min.

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