Sodium Carbonate → (R)-tert-butyl 1-(4-(2-cyano-5-fluorobenzyl)-6-methyl-5-oxo-4,5-dihydro-1,2,4-triazin-3-yl)piperidin-3-ylcarbamate

Beteiligte Stoffe

Reaktionsschritte

To a mixture of Na2CO3 (53 mg, 0.50 mmol) and Pd(OAc)2 (3 mg, 0.013 mmol) in NMP (0.5 mL) was added i-PrOH (3 drops) and water (2 drops). The mixture was stirred at RT for 5 min. A solution of (R)-tert-butyl 1-(4-(2-bromo-5-fluorobenzyl)-6-methyl-5-oxo-4,5-dihydro-1,2,4-triazin-3-yl)piperidin-3-ylcarbamate (18, 246 mg, 0.496 mmol) in NMP (1.0 mL) was added. The mixture was heated to 140° C. and then K4[Fe(CN)6].3H2O (209 mg, 0.496 mmol) was added. The mixture was heated at 140° C. for 12 h. After cooling to RT, the mixture was diluted with water (10 mL), and extracted with EtOAc (20 mL×2). The combined extracts were washed with brine, dried over MgSO4, and concentrated to give crude product. This was purified by column chromatography on silica gel, and eluted with 20-35% EtOAc in petroleum ether to provide (R)-tert-butyl 1-(4-(2-cyano-5-fluorobenzyl)-6-methyl-5-oxo-4,5-dihydro-1,2,4-triazin-3-yl)piperidin-3-ylcarbamate (20). MS: m/z, 418 (20%), 443 (100%, M+1), 465 (95%, M+23).

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