Cesium carbonate → [2-(4-Amino-3-nitro-phenyl)-ethyl]-carbamic acid benzyl ester

Participants

Reaction Steps

A flask was charged with 4-bromo-2-nitroaniline (505 mg), potassium (2-(((benzyloxy)carbonyl)amino)ethyl)trifluoroborate (745 mg), Pd(OAc)2 (25.3 mg), 2-(dicyclohexylphosphino)-2′,6′-dimethoxybiphenyl (94.6 mg) and Cs2CO3 (2.2 g) in dioxane/water (20 mL/2 mL). The reaction mixture was refluxed for 92 h, cooled down, diluted with EA and washed with water and brine. The aq. layers were extracted with EA, the combined org. layers were dried (MgSO4), filtered off and evaporated to dryness. The residue was purified by CC (Biotage, SNAP 25 g cartridge, solvent A: Hept; solvent B: EA; gradient in % B: 10 for 3CV, 10 to 30 over 3CV, 30 for 4CV, 30 to 50 over 3CV, 50 for 5CV) to afford 143 mg of red oil. LC-MS (B): tR=0.85 min; [M]+: 316.07.

Provenance & Evidence