3,3,3-Trifluoro-2-hydroxy-2-methylpropanoic acid → 3-Amino-6-bromo-N'-(3,3,3-trifluoro-2-hydroxy-2-methylpropanoyl)-5-(trifluoromethyl)picolinohydrazide

Participants

Reaction Conditions

Reaction Steps

A cooled (0° C.) solution of 3-amino-6-bromo-5-(trifluoromethyl)picolinohydrazide (Intermediate H) (15 g, 50.2 mmol) in dry NMP (50 ml) was treated with 3,3,3-trifluoro-2-hydroxy-2-methylpropanoic acid (8.72 g, 55.2 mmol), HATU (20.98 g, 55.2 mmol) followed by dropwise addition of TEA (15.38 ml, 110 mmol) over 10 minutes. The orange solution was stirred at 0° C. and allowed to warm to RT and stirred for 3 days. The reaction mixture was partitioned between EtOAc (200 mL) and 1M NaOH (200 mL), shaken and separated. The organic portion washed with brine (100 mL), dried (MgSO4) and concentrated in vacuo to give an orange oil. The oil was taken up in methanol (50 mL) and triturated with water (300 mL) to afford the title compound as a yellow solid;

Provenance & Evidence