These common heterocyclic compound, 3994-50-1, name is 1-Methyl-4-nitro-1H-pyrazole, its traditional synthetic route has been very mature, but the traditional synthetic route has various shortcomings, such as complicated route, low yield, poor purity, etc, below Introduce a new synthetic route. Recommanded Product: 3994-50-1
To a solution of tert-butyl N- [(15)-i -(5 -bromopyridin-3 -yl)but-3 -en- l-yl]carbamate (1.0 g, 3.06 mmol), prepared as described in Intermediate 26, in dioxane (10ml) was added 1-methyl-4-nitro-1H-pyrazole (0.427 g, 3.36 mmol), di(adamantan-1-yl)(butyl)phosphine (0.164 g, 0.458 mmol), K2C03 (1.267 g, 9.17 mmol) and pivalic acid(0.106 ml, 0.917 mmol). The reaction mixture was purged with Ar. Pd(OAc)2 (0.069 g,0.306 mmol) was added and the solution was stirred at 100 C. After 4 h, the reactionwas quenched with water (20 ml) and extracted with EtOAc (3 x 50 ml). The combinedorganic layers were washed with brine (20 ml), dried (MgSO4), filtered, and concentrated.The residue was purified by normal phase chromatography using heptanes and EtOAc aseluents to give tert-butyl N-[( 15)-i -[5 -(1 -methyl-4-nitro- 1 H-pyrazol-5 -yl)pyridin-3 -yl]but-3-en-i-yl]carbamate (0.85 g, 74%) as a white foam. MS(ESI) m/z: 374.5 (M+H).?H NMR (500MHz, CDC13) oe 8.74 (d, J=i .9 Hz, 1H), 8.57 (d, J=i .9 Hz, 1H), 8.25 (s,1H), 7.72 (t, J=i.9 Hz, 1H), 5.73 (ddt, J=17.i, 10.2, 7.2 Hz, 1H), 5.26 – 5.17 (m, 2H),4.99 (br. s., 1H), 4.93 – 4.84 (m, 1H), 3.80 (s, 3H), 2.75 – 2.52 (m, 2H), 1.43 (br. s., 9H).
The synthetic route of 1-Methyl-4-nitro-1H-pyrazole has been constantly updated, and we look forward to future research findings.