Commercial Synthesis of a Pyrrolotriazine-Fluoroindole Intermediate to Brivanib Alaninate: Process Development Directed toward Impurity Control (vol 18, pg 89, 2014)

The development of a practical, commercial process for the preparation of 4-fluoro-2-methyl-indol-5-ol and its subsequent coupling with a pyrrolotriazine to form an advanced intermediate of the oncology therapy brivanib alaninate is described. A key aspect is the multikilogram-scale preparation of the fluoroindole intermediate from trifluoronitrobenzene and the subsequent coupling while achieving impurity minimalization. As brivanib alaninate is a high-dose drug, the synthesis of high. quality API with low levels of impurities is critical.