preparation | in 4N hydrochloric acid in dioxane (8.00 ML, MOL HCl) tert-butyl 2-(4-methoxybenzyl) hydrazine carboxylate (324g,1.09mol) dissolved in a minimum amount of dioxane was added slowly over 1 hour. A precipitate was gradually formed. The solution was stirred at 20±5 °c for 16 hours. The solid was collected by filtration. The solid was homogenized in heptane (2000ml) and the solid was isolated by filtration. Dry the solid using nitrogen to give the title compound 4-methoxybenzhydrazide dihydrochloride (242.3g,1.08mol,98%). |