A mixture comprising 7-chloro-2,3-di-p-tolylpyrido[2,3-b]pyrazine (step 1) (2.5 g, 7.24 mmol), ethyl boronic acid (0.748 g, 10.14 mmol) and K2CO3 (2.9 g, 21.73 mmol) was degassed with argon and treated with Pd(PPh3)4(0.418 g, 0.362 mmol). The resulting mixture was flushed with argon and heated at 100° C. for 12 h and heating continued overnight. The reaction mixture was diluted with water and extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulphate and concentrated under vacuum. Purification of the crude product by chromatography on silica eluting with 10% EtOAc in hexane afforded the titled compound;
