Phosphoric Acid → HCID 86683823, compound

Participants

Reaction Steps

To a solution of isoamyl alcohol (100 g, 1.13 mol) and triethylamine (173 mL, 1.25 mol) in tetrahydrofuran (1.13 L) was added dropwise methanesulfonyl chloride (136 g, 1.19 mol) with keeping the internal temperature below 17° C. over 1 hour, and the reaction mixture was stirred at the same condition for 1 hour. To the resultant was added dropwise water (1.0 L) with keeping the internal temperature below 13° C., and the mixture was extracted with toluene (1.7 L). The organic layer was dried over anhydrous MgSO4 and the solvent was evaporated under reduced pressure to give a crude product of Compound (Igg) (198 g), which was used in the next step without further purification. The resulting Compound (Igg) and hydrazine monohydrate (339 g, 6.77 mol) were dissolved in ethanol (1.13 L), and the reaction mixture was stirred at 50° C. (internal temperature) for 2 hours. The mixture was cooled to room temperature, and partitioned between chloroform (2.26 L) and water (339 mL). The chloroform layer was washed with water (339 mL, ×2). To the solution of chloroform was added phosphoric acid (85%, 130 g, 1.13 mol) at room temperature, and the solvent was evaporated under reduced pressure. To the obtained white-solid was added 2-propanol (300 mL), and the solvent was evaporated under reduced pressure (×3). To the concentrated residue was added 2-propanol (1.13 L). The mixture was stirred for 1.5 hours at 45° C. (internal temperature) and then stirred overnight with slowly cooling to room temperature. The resulting precipitate was collected by filtration, washed with cold 2-propanol (100 mL, ×2), and dried under reduced pressure to give the title Compound (IIgg) (181 g, 80%) as a white powder.

Provenance & Evidence