Sodium Carbonate → [2-(2-Chloropyrimidin-4-yl)-benzo[b]thiophen-6-ylmethyl]-carbamic acid tert-butyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Benzo[b]thiophen-6-ylmethyl-carbamic acid tert-butyl ester (3.6 g, 13.8 mmol) is dissolved in THF (100 mL) and cooled to −78° C. Triisopropylborate (8.5 mL) is added, followed by lithium diisopropylamine solution (27 mL of 2.0 M solution), and the reaction is allowed to slowly warm to room temperature over two hours. The reaction is stirred at room temperature for two hours at which time 2,4-dichloropyrimidine (4.59 g, 30.8 mmol), 1,1′-bis(diphenylphosphino)ferrocene (388 mg, 0.700 mmol), palladium (II) acetate (164 mg, 0.730 mmol) and sodium carbonate (28 mL of 2.0 N solution) are added. The reaction is heated for 20 hours at 70° C. After the reaction solution is cooled to 25° C., water (100 mL) is added. The mixture is extracted with dichloromethane and the extracts are evaporated. The resulting solid is subjected to chromatography on silica gel, eluting with EtOAc/hexanes 5-50%, to give the title compound (1.47 g, 28% yield). ES+(m/z) 376 (35Cl) and 378 (37Cl) [M+H].

Herkunft & Nachweise