2-(Tri-n-butylstannyl)oxazole → Methyl 3-amino-6-(oxazol-2-yl)-5-(trifluoromethyl)picolinate

Participants

Reaction Steps

A solution of 3-amino-6-bromo-5-trifluoromethyl-pyridine-2-carboxylic acid methyl ester (Intermediate A4) (500 mg, 1.672 mmol), 2-(tributylstannyl)oxazole (0.704 ml, 3.34 mmol) and tetrakis(triphenylphosphine)palladium(0) (193 mg, 0.167 mmol) in dioxane (10 ml) was heated at reflux for 13 hours. After cooling to room temperature over 8 hours, the solvent was evaporated and the resulting residue triturated with hot methanol to remove a yellow solid impurity. The remaining crude material was used without further purification. LC-MS: Rt 0.95 min; MS m/z 288 [M+H]+; Method 2 minLC_v003.

Provenance & Evidence