2-hydroxy-2-(trifluoromethyl)butanehydrazide

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To hydrazide (34.07 g, 183 mmol) of step 2 in 275 mL of water was added KHCO3 (18.33 g, 183 mmol) followed by BrCN (19.39 g, 183 mmol) portionwise. After 3 h, the solid was filtered, washed with cold water and dried to afford the title compound. Additional compound could be recovered from the aqueous phase by extraction (ether-hexane, 1:1). 1H NMR (400 MHz, acetone-d6): δ 6.54 (s, 2H), 6.01 (s, 1H), 2.22 (m, 1H), 2.08 (m, 1H) and 0.99 (m, 3H). the solid was filtered washed with cold water dried

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: The ethyl ester of step 1 (50.04 g, 250 mmol) and hydrazine hydrate (25.03 g, 50 mmol) were heated at 80° C. for 18 h. The excess hydrazine was removed under vacuum and the crude product was filtered through a pad of silica gel with EtOAc-Hexane (ca. 3 L) to furnish the title compound. 1H NMR (400 MHz, acetone-d6): δ 9.7 (s, 1H), 6.10 (s, 1H), 2.25 (m, 1H), 1.85 (m, 1H) and 0.95 t, (3H). The excess hydrazine was removed under vacuum the crude product was filtered through a pad of silica gel with EtOAc-Hexane (ca. 3 L)