1-(1H-INDAZOL-3-YL)ETHANONE

To a solution of N-methoxy-N-methyl- 1 H-indazole-3 -carboxamide (950mg, 4.63mmol, 1 .Oeq.) in dry THF, the mixture was cooled down to 0°C. Methylmagnesium bromide (7.7m1, 23.l7mmol, 5.Oeq.) was added dropwise to the mixture at 0°C. The resulting mixture was stirred at r.t. for 12 h. Sat. NH4C1 solution (5m1) was added to the mixture. The solvent of the mixture was removed under vacuum, and the resulting residue was purified by column chromatography EAJPE = 1/2) to provide 1-(1H-indazol-3- yl)ethanone (610 mg, 82.3 percent yield) as yellow solid.To a stirred solution of compound C (700 mg, 3.4 mmol, 1 eq) in dry THF (40 mL) was added methyl magnesium bromide (1 M in diethyl ether, 11 mL, 10.2 mmol, , 3 eq) drop wise at 0 °C and the resulting mixture was stirred for 18 h at 23 °C. The reaction mixture was quenched with saturated aq. NHFollowing a prenominal variation in the reported procedure refPreviewPlaceHolder[26], isobutyl chloroformate (0.79 g, 5.88 mmol) and N-methylmorpholine (0.59 g, 5.88 mmol) were added to a solution of 1H-indazole-3-carboxylic acid (0.6 g, 3.70 mmol) in anhydrous THF (15 mL) under nitrogen atmosphere at -20 °C, and the mixture was stirred for 4 h. To this mixture was added N, O-dimethylhydroxylamine hydrochloride (0.54 g, 5.55 mmol) suspended in 5 mL triethylamine. The reaction was then stirred at room temperature for 6 h, concentrated under vacuum and suspended in 20 mL n-hexane. The white precipitates (Winreb amide) formed were filtered off, dried and immediately transferred to a three neck flask containing 10 mL anhydrous THF cooled to -78 °C. To this was added methyl magnesium bromide (12percent in THF) (19 mL, 18.5 mmol). The reaction was allowed to stir at -78 °C for 2 h and then at room temperature for 5 h. The completion of the reaction was monitored by TLC. The reaction was quenched by slow addition of saturated aqueous solution of ammonium chloride followed by extraction with ethyl acetate (3 .x. 20 mL). The combined organic layer was dried over magnesium sulfate and concentrated under vacuum. The resulting viscous mass was purified by column chromatography using hexane: ethyl acetate (85:15) solvent system to obtain desired acetyl derivative (0.32 g, 55percent); m.p. 182-185 °C (Lit. m.p. 184-186 °C) refPreviewPlaceHolder[26]; RAdd raw material 5 (4.1 g, 20 mmol) to a two-necked flask, evacuate under argon, replace three times, add anhydrous THF, cool the reaction to -10 C, and slowly add methyl magnesium chloride (20 mL, 3.0 M in THF), after the completion of the dropwise addition, the reaction was carried out to room temperature. After the reaction was completed, the reaction was quenched by adding a saturated ammonium chloride solution at a low temperature, and the organic layer was collected, washed with saturated brine, dried over sodium sulfate, and concentrated with EA/PE (v/v , 1:10) Eluent column chromatography to obtain a pale yellow solid 6 (2.56 g, 80%)6 (2.4 g, 15 mmol), cuprous iodide (572 mg, 3 mmol), L-valine (690 mg, 6 mmol), potassium carbonate (4.14 g, 30 mmol) were added to a two-neck bottle, and argon gas was added to 30 mL. In DMSO, 3-bromopyridine (3.56 g, 22.5 mmol) was added at room temperature to raise the temperature to 120 C.After the completion of the reaction, the mixture was cooled to room temperature, and then added with 50 mL of ethyl acetate. The mixture was stirred for 20 min, and the residue was evaporated to dryness. A yellow solid 7 (2.92 g, 82%).

Molecular Weight:160.17
XLogP3:1.6
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:2
Rotatable Bond Count:1
Exact Mass:160.063662883
Monoisotopic Mass:160.063662883
Topological Polar Surface Area:45.8
Heavy Atom Count:12
Complexity:193
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes