Cesium carbonate → tert-butyl (2-chloro-5-cyano-3-(1,1-dioxidotetrahydro-2H-isothiazolo[2,3-a]pyrazin-5(3H)-yl)phenyl)carbamate

Participants

Reaction Conditions

Reaction Steps

A mixture of tert-butyl (3-bromo-2-chloro-5-cyanophenyl)carbamate (160 mg, 0.482 mmol), hexahydro-2H-isothiazolo[2,3-a]pyrazine 1,1-dioxide (85 mg, 0.482 mmol), Pd2dba3 (44.2 mg, 0.048 mmol), BINAP (90 mg, 0.145 mmol), and Cs2CO3 (471 mg, 1.447 mmol) in Dioxane (5 mL) was evacuated and filled with nitrogen 3× and heated at 105° C. overnight. The reaction mixture was filtered through a plug of celite and the filtrate was concentrated. The crude product was purified by flash chromatography on silica gel using an automated ISCO system (40 g column, eluting with 1-10% Methanol in DCM) to give tert-butyl (2-chloro-5-cyano-3-(1,1-dioxidotetrahydro-2H-isothiazolo[2,3-a]pyrazin-5(3H)-yl)phenyl)carbamate (77 mg)

Provenance & Evidence