ChemicalBook CAS DataBase List 2-Chloro-3-fluoronitrobenzene

2-Chloro-3-fluoronitrobenzene synthesis

6synthesis methods

Product Name:2-Chloro-3-fluoronitrobenzene
CAS Number:21397-07-9
Molecular formula:C6H3ClFNO2
Molecular Weight:175.54

402-67-5

21397-07-9

General procedure for the synthesis of 2-chloro-3-fluoronitrobenzene from 3-fluoronitrobenzene: To a solution of 3-fluoronitrobenzene (2 g, 14.2 mmol) in tetrahydrofuran (THF, 30 mL) was slowly added a solution of N-chlorosuccinimide (5.69 g, 42.6 mmol) in THF (20 mL) at -78 °C. Subsequently, NaHMDS (28.4 mL, 28.4 mmol) in a 1 M solution of THF was added dropwise while ensuring that the internal temperature of the reaction system was maintained below -75 °C. The reaction mixture was stirred continuously at -78 °C for 30 min. Upon completion of the reaction, the mixture was partitioned between 5% hydrochloric acid and ethyl acetate. The organic layers were combined, dried with anhydrous magnesium sulfate (MgSO4), filtered and the solvent evaporated. The resulting solid was purified by silica gel column chromatography with the eluent being a hexane solution of 20% ethyl acetate, resulting in the target product 2-chloro-3-fluoronitrobenzene (231 mg, 9.2% yield). The structure of the product was confirmed by EI-MS, m/z 176.5 (M+).

402-67-5 Synthesis

402-67-5
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$6.00/5g

21397-07-9
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$30.00/1g

Yield:21397-07-9 79.8%

Reaction Conditions:

with hexachloroethane;lithium tert-butoxide in N,N-dimethyl-formamide at 60; for 4 h;Inert atmosphere;regioselective reaction;

Steps:

Synthetic procedure of compound 6

A solution of 1-fluoro-3-nitrobenzene (1.41g, 10mmol), t-BuOLi (2.00g, 25mmol) and C₂Cl₆ (4.73g, 20 mmol) in 15ml dry DMF was stirred for 4h at 60°C under N₂atmosphere. Ethyl acetate was added and the resulting organic solution was washed by 1M HCl, saturated NaHCO₃ and brine successively. The solvent was removed under reduced pressure and the residue was purified on column chromatography (eluted by 0.5% ethyl acetate in petroleum ether) to obtain 6 as a colorless oil. Yield: 79.8%, ¹H NMR (400 MHz, CDCl₃) δ 7.77-7.69 (m, 1H, Ph-H), 7.48-7.41 (m, 2H, Ph-H).

References:

Wei, Wei;Zhou, Shaa;Cheng, Dandan;Li, Yuxin;Liu, Jingbo;Xie, Yongtao;Li, Yonghong;Li, Zhengming [Bioorganic and Medicinal Chemistry Letters,2017,vol. 27,# 15,p. 3365 - 3369] Location in patent:supporting information