The product from step A (3.09 g, 10.79 mmol), sodium acetate (0.879, 10.7 mmol) and (4-chloro-3-methylphenyl)hydrazine hydrochloride (2.24 g, 11.6 mmol) were mixed in dioxane (25 mL) and acetic acid (25 mL). The reaction mixture was warmed at 90° C. with stirring for 16 h, cooled to rt and the volatiles were removed. Purification of the residue on SiO2 (5 to 60% ethyl acetate, hexanes) afforded the title compound, which was used without further purification. HPLC/MS: 335.0, 337.0 (M-55), Rt=3.40 (LC4).
