Aluminium lithium hydride → 4-Chlorophenylurea

Beteiligte Stoffe

Reaktionsschritte

To a stirred solution of Example C (1.60 g, 3.63 mmol) in THF (200 mL) was added LiAlH4 powder (413 mg, 10.9 mmol) at −10° C. under N2. The mixture was stirred for 2 h and excess LiAlH4 was quenched by adding ice. The solution was acidified to pH=7 with dilute HCl. Solvents were slowly removed and the solid was filtered and washed with EtOAc (200+100 mL). The filtrate was concentrated to yield 1-{3-tert-butyl-1-[3-hydroxymethyl)phenyl]-1H-pyrazol-5-yl}-3-(4-chlorophenyl)urea (1.40 g, 97%). 1H NMR (DMSO-d6): δ 9.11 (s, 1H), 8.47 (s, 1H), 7.47-7.27 (m, 8H), 6.35 (s, 1H), 5.30 (t, J=5.6 Hz, 1H), 4.55 (d, J=5.6 Hz, 2H), 1.26 (s, 9H); MS (ESI) m/z: 399 (M+H+).

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