1,2-Dichloro-4-fluorobenzene

clear colorless to slightly yellow liquid

General procedure: To a 4 ml borosilicate vial, equipped with a stir bar, was added Ir[dF(CF3)ppy]2(dtbpy)PF6 (2.4 mg, 2.1 mumol, 1.0 mol%) (dF(CF3)ppy, 2-(2, 4-difluorophenyl)-5-(trifluoromethyl)pyridine; dtbpy, 4, 4'-di-tert-butyl-2, 2'-bipyridine)) and an aryl (tetrafluoro)thianthrenium salt (0.200 mmol, 1.00 equiv.). Under N2 atmosphere, Cu(MeCN)4BF4 (94.4 mg, 0.300 mmol, 1.50 equiv.), anhydrous CsF (36.4 mg, 0.240 mmol, 1.20 equiv.) and anhydrous acetone (2.0 ml, 0.10 M) were added into the reaction vial. Subsequently, the vial was capped and placed 5 cm away from two 34 W blue light-emitting diode (LEDs). The temperature was kept at approximately 30 C through cooling with a fan. After being stirred for 20 h, the reaction mixture was diluted with CH2Cl2 (2 ml) and the resulting mixture was filtered through a short pad of Celite using CH2Cl2 (5 ml) as eluent. The filtrate was collected and concentrated by rotary evaporation. The residue was purified by chromatography on silica gel to afford the fluorinated product. Note that for the optimal results, the use of anhydrous CsF is important for the reaction. When CsF was weighed under ambient atmosphere, the yield of the fluorinated product was lower and the yield of the hydrodefunctionalized product was higher. Schlenk techniques can be used to avoid moisture. For convenience, we stored and weighed the CsF in a N2-filled glove box; the reactions can be performed outside a glove box.General procedure: A mixture of l-fluoro-4-nitrobenzene (297A) (1.42 g, 10 mmol), 4, 4-difluoropiperidine hydrochloride (297B) (1.6 g, 10 mmol), and K2CO3 (4.14 g, 30 mmol) in DMF (80 mL) was stirred at 70 C overnight. After cooled down to room temperature, the mixture was diluted with H2O (200 mL) and extracted with ethyl acetate (80 mL x 2). The combined organic layers was washed with brine (200 mL), dried over anhydrous sodium sulfate, concentrated, and purified with flash column chromatography on silica gel (ethyl acetate in petroleum ether, 20% v/v) to afford Compound 297C. LC-MS (ESI) m/z: 243 [M+H]+.

Intermediate for medicine, pesticide, liquid crystal material.

Molecular Weight:164.99
XLogP3:3.5
Hydrogen Bond Acceptor Count:1
Exact Mass:163.9595836
Monoisotopic Mass:163.9595836
Heavy Atom Count:9
Complexity:97.1
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes