Researchers who often do experiments know that organic synthesis is a process of preparing more complex target molecules from simple raw materials through one or more chemical reactions. Generally, it requires fewer steps, and cheap raw materials. 459-22-3, name is 4-Fluorophenylacetonitrile, A new synthetic method of this compound is introduced below., Recommanded Product: 4-Fluorophenylacetonitrile
Reagents and conditions: (a) EtONa, EtOH, refluxing; (b) CH3NHNH2, HC1, EtOH,MW, 100C, 40 mm; (c) Fmoc-(R)-3-amino-4-(4-fluorophenyl)butanoyl chloride,DCM, then DBU. A mixture of 1.8 ml (15 mmol) of ethyl 2,2,2-trifluoroacetate (ib)and 0.96 g (7.1 mmol) of 2-(4-chloro-2-fluorophenyl)acetonitrile (3a) in 10 ml ofethanol was slowly dropped into hot solution of 1.2 g of sodium in 20 ml of ethanol.The mixture was refluxed overnight. The solution turns red. After cooled down, thesolution was poured into 250 ml of cold water acidified with 10 ml concentrated HC1.The mixture was extracted with ethyl acetate. The ethyl acetate extraction was washedwith water, brine and dried over Mg504. Ethyl acetate was removed and the residualreddish oil of 4,4,4-trifluoro-2-(4-fluorophenyl)-3 -oxobutanenitrile (3c) was obtained in1.3 g. The raw material was dissolved in 10 ml of ethanol and used in next step withoutfurther purification. A mixture of 2.8 ml of the above ethanol solution and 125pi ofmethylhydrazine with 0.2 ml of concentrated HC1 was irradiated in microwave oven at100C for 40 mm. The solution was treated with saturated NaHCO3 and extracted byethyl acetate. The organic layer was washed with water, brine, dried over Mg504 andconcentrated. The yellow residue was subjected to flash chromatography purificationwith MeOHIDCM to give 165 mg of 3-(trifluoromethyl)-4-(4-fluorophenyl)-1-methyl-1H-pyrazol-5-amine (3d) as light yellow solid. ?H NMR (500 MHz, CDC13) 7.32 (s,2H), 7.14 (t, J = 8.0 Hz, 2H), 3.76 (d, J = 33.5 Hz, 3H), 3.65 (s, 2H). M/Z =260.6(M+1). To a solution of Fmoc-(R)-3-amino-4-(4-fluorophenyl)butanoyl chloride (43mg, 0.20 mmol) produced from Fmoc-(R)-3-amino-4-(4-fluorophenyl)butanoic acid(from Chem Impex International) and thionyl chloride in 10 ml of anhydrous DCM were slowly added 3 -(trifluoromethyl)-4-(4-fluorophenyl)- 1-methyl-i H-pyrazol-5 – amine obtained as described above (39 mg, 0.15 mmol) in 5 ml of anhydrous DCM. The reaction mixture was stirred at room temperature overnight. The reaction mixture was quenched with methanol and solvents were removed. The residue was purified via silicagel with MeOHIDCM to obtained Fmoc protected product. Fmoc protected product was dissolved in 10 ml of ethyl acetate and 0.15 mmol of DBU was added. After 20mm 20 ml of ethyl acetate was added and mixture was washed with 20 ml of water. The organic layer was collected and solvent was removed. The residue was dissolved in MeOH and acidified with 0.2N HC1. The solution was purified via preparatory RP-HPLC, elutingwith H20/CH3CN gradient (+0.05% TFA). Product fractions are collected and concentrated. The residue is dissolved in a small amount of 2M HC1 in methanol and, after concentration in vacuo, 50 mg of Compound (3) is obtained as an HC1 salt. ?H NIVIR (500 IVIFIz, MeOD) 7.40 – 7.08 (m, 6H), 7.02 (t, J = 8.8 Hz, 2H), 3.77 (d, J = 15.4 Hz, 3H), 3.37 (dt, J = 7.9, 6.6 Hz, 1H), 2.64 (m, 2H), 2.42 (m, 2H). M/Z 439.4(M+i).
The basis of chemical reaction formula synthesis, the synthesis route is composed of some specific reactions and combined according to certain logical thinking. We look forward to the emergence of more reaction modes in the future.