Water → HCID 58009875, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of 2-bromo-5-tosyl-5H-pyrrolo[2,3-b]pyrazine (75 g, 213 mmol), PdCl2(dppf)-CH2Cl2 adduct (8.69 g, 10.6 mmol) and (E)-styrylboronic acid (39.4 g, 266 mmol) in THF (600 mL) was added Na2CO3 (27.1 g, 256 mmol) and water (300 mL). The reaction mixture was degassed with nitrogen for about 45 min. The reaction mixture was heated to about 65° C. for about 16 h then PdCl2 (dppf)-CH2Cl2 adduct (3.50 g, 4.29 mmol) was added. After about 18 h, the reaction was cooled to ambient temperature. The layers were separated and the organic layer was concentrated under reduced pressure. The residue was triturated in EtOH (300 mL)/DCM (100 mL) and filtered. The precipitate was triturated in hot EtOH (400 mL) and filtered, then washed with EtOH (200 mL) and Et2O (400 mL). The filtrates were recombined, concentrated under reduced pressure, and the resulting residue was triturated in EtOH (300 mL)/DCM (100 mL) and stirred overnight while allowing the DCM to slowly evaporate. The mixture was filtered and washed with EtOH (100 mL) and Et2O (100 mL) to give a second crop. The combined filter cakes were dried under vacuum to provide (E)-2-styryl-5-tosyl-5H-pyrrolo[2,3-b]pyrazine (72.7 g, 91%) as a tan solid: LC/MS (Table 2, Method a) Rt=2.66 min; MS m/z: 376 (M+H)+.

Provenance & Evidence