Stannous Chloride → (3-(Trifluoromethoxy)phenyl)hydrazine hydrochloride

3-(Trifluoromethoxy)aniline (3.68 ml) was dissolved in 6 M hydrochloric acid (71 ml), and an aqueous solution (4.7 ml) of sodium nitrite (2.08 g) was added dropwise over 20 min at −5° C. Tin (II) chloride (1.954 ml) was dissolved in 6 M hydrochloric acid (25 ml), and the solution was cooled to −5° C., and added quickly to the above-mentioned reaction mixture at −5° C. The mixture was stirred at −5° C. for 2 hr, and the precipitated solid was collected by filtration, washed with 0.1M hydrochloric acid, and dried under reduced pressure to give the title compound (2.72 g).