Dimethylformamide → (R,R)-N-[4-bromo-3-(4-ethoxyphenyl)isothiazol-5-yl]-2-methylcyclopropane-carboxamide

Participants

Reaction Conditions

Reaction Steps

Degas a solution of (R,R)—N-[3,4-dibromoisothiazol-5-yl]-2-methylcyclopropane-carboxamide (0.500 g, 1.471 mmol), (4-ethoxyphenyl)boronic acid (0.485 g, 2.941 mmol), DMF (3 mL) and toluene (29 mL) with nitrogen. Add sodium carbonate (2 M) (4.41 mmol) and Pd(PPh3)4 (0.255 g, 0.221 mmol); then seal under nitrogen. Heat at 60° C. overnight. Add 100 mg of Pd(PPh3)4 and heat for 1 more day. Dilute with EtOAc and wash with brine. Separate and evaporate. Chromatography on silica gel, eluting with 15-50% EtOAc in hexane, followed by crystallization from EtOAc and hexane affords (R,R)—N-[4-bromo-3-(4-ethoxyphenyl)isothiazol-5-yl]-2-methylcyclopropane-carboxamide. Yield: 53.5% ES-MS: 380.0 (m+1).

Provenance & Evidence