Methylhydrazine → HCID 178481737, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of ethyl 3-oxo-3-(pyridin-2-yl)propanoate (25.00 g, 129 mmol, Matrix Scientific) in EtOH (60 mL) was added methylhydrazine (6.81 mL, 129 mmol). The mixture was heated at about 85° C. for about 3 h then cooled to rt and concentrated at rt under reduced pressure. The material was triturated with Et2O (40 mL). The solids were collected by filtration then washed with Et2O to give 1-methyl-3-(pyridin-2-yl)-1H-pyrazol-5-ol (17.80 g, 79%). The filtrate was concentrated under reduced pressure then the material was triturated with 1:1 DCM/Et2O. The solids were collected by filtration and washed with Et2O to give a second crop of 1-methyl-3-(pyridin-2-yl)-1H-pyrazol-5-ol (1.20 g, 5%): LC-MS (Table 1, Method g) Rt=1.05 min, m/z 176 (M+H)+; 1H-NMR (DMSO, Bruker 400 MHz) δ 11.05 (s, 1H), 8.50-8.47 (m, 1H), 7.83-7.80 (m, 1H), 7.78-7.69 (m, 1H), 7.24-7.19 (m, 1H), 5.90 (s, 1H), 3.57 (s, 3H).

Provenance & Evidence