Cesium carbonate → 6-Chloro-4-(6,7-dihydro-4H-pyrazolo[5,1-c][1,4]oxazin-2-ylamino)-2-methylpyridazin-3(2H)-one

Participants

Reaction Steps

A mixture of 6,7-dihydro-4H-pyrazolo[5,1-c][1,4]oxazin-2-amine 129b (0.8 g, 5.76 mmol), xantophos (360 mg, 0.623 mmol), Pd2 dba3 (384 mg, 0.42 mmol), 4-bromo-6-chloro-2-methylpyridazin-3(2H)-one (1.28 g, 5.76 mmol) and Cs2CO3 (5.05 g. 17.3 mmol) in 1,4-dioxane (40 mL) was heated at reflux for 2 h. After the completion of the reaction, the mixture was filtered off, and washed with MeOH (60 mL). The filtrate was evaporated in vacuo. The residue was purified on reverse phase Combi-flash to give 132a (1.3 g, 81%). MS: [M+H]+ 282.

Provenance & Evidence