Sodium cyanoborohydride → N-Methyl-N-((1-methyl-3-nitro-1H-pyrazol-5-yl)methyl)oxetan-3-amine

Participants

Reaction Conditions

Reaction Steps

To a mixture of 302a (170 mg, 1 mmol) in methanol (4 mL), ZnCl2 (1 mmol/L in diethyl ether) (2 mL, 2 mmol) and oxetan-3-one (150 mg, 2 mmol) were added at room temperature under nitrogen protection, followed by the addition of NaBH3CN (130 mg, 2 mmol). The reaction mixture was warmed to 50° C. and stirred for 3 h. The mixture was then cooled to room temperature and the solvent was removed. The residue was purified on flush column eluting with 50:1 methylene chloride/methanol to afford 302b as a yellow solid (180 mg, 80%, two steps). LCMS: (M+H)+ 227. 1H NMR (500 MHz, DMSO) δ 6.99 (s, 1H), 4.52 (t, J=6.5, 2H), 4.42 (t, J=6, 2H), 3.98 (s, 3H), 3.63 (m, 1H), 3.50 (s, 2H), 2.03 (s, 3H).

Provenance & Evidence