Cesium carbonate → HCID 86708475, compound

Participants

Reaction Conditions

Reaction Steps

(I11A): Tert-butyl (3-bromo-2-chloro-5-cyanophenyl)carbamate (Intermediate 1) (4.5 g, 13.57 mmol), Pd2 dba3 (0.746 g, 0.814 mmol), BINAP (0.676 g, 1.086 mmol) and Cs2CO3 (8.84 g, 27.1 mmol) were suspended in toluene (12.0 mL) at room temperature. Tert-butyl piperazine-1-carboxylate (3.29 g, 17.64 mmol) was added and the reaction was degassed and purged with Argon, degassed for 6 times. The reaction mixture was heated at 105° C. for overnight. On completion of the reaction, the reaction mixture was cooled to room temperature, diluted with ethyl acetate, filtered through celite and concentrated. The Crude material was purified by column chromatography (ISCO), using 0-10% ethyl acetate-hexane as eluent. Pure fractions were concentrated to obtain tert-butyl 4-(3-((tert-butoxycarbonyl)amino)-2-chloro-5-cyanophenyl)piperazine-1-carboxylate (3.0 g) as an off-white solid.

Provenance & Evidence