3-Bromo-4-fluorobenzotrifluoride

clear colorless liquid

In a 2000ml three-necked flask, 400g of concentrated sulfuric acid, p-fluorobenzotrifluoride 400g, lithium bromide 10g, ferric bromide 20g, tetrabutylammonium bromide 10g, Bromine 234.14g, temperature control 35-45 ° C, the reaction 6h, GC detection of raw materials 0.36percent. Cooled to below 30 , transferred to 2000ml separation funnel, stationary 1h, the acid was separated, the crude product was placed in 2000ml bottle, 1000g of water was added under stirring, dropping 10percent sodium hydroxide solution to adjust PH = 7, 548.6 g of 3-bromo-4-fluorobenzotrifluoride was isolated at a constant rate of 92.56percent with 97.9percentThe product was purified by vacuum distillation 526.33g, distillation yield 95.94percent.3-Bromo-4-fluorobenzotrifluoride (65.8 mmol), bis(pinacolato)diboron (32.9 mmol), Pd2(dba)3 (0.33 mmol), SPhos (1.32 mmol) and tribasic potassium phosphate (197 mmol) are stirred under nitrogen in a dioxane/water mixture (300 ml/20 ml) of 110 C. for 16 hours. The insoluble constituents of the reaction mixture are subsequently removed by filtration, the material on the filter being washed with dioxane. The solvent of the filtrate is removed and the residue obtained is dissolved in dichloromethane and filtered through a little silica gel. The product is obtained as a yellow solid. 1H NMR (500 MHz, chloroform-d) 5=7.72-7.69 (m, 4H), 7.34-7.31 (m, 2H) ppm.j00298J A flask was charged with t-butyl 4-hydroxypiperidine-1-carboxylate (2.0 g, 9.94 mmol, 1.00 equiv) and THF (40 mL). Then sodium hydride (60% in oil, 0.800 g, 20.0 mmol, 2.00 equiv) was added at 0 C. The resulting solution was stirred for 1 hour at room temperature and 2-bromo- 1 -fluoro-4-(trifluoromethyl)benzene (3.20 g, 13.2 mmol, 1.30 equiv) was added. The resulting solution was stirred overnight at room temperature and quenched by water (20 mL), as described in Example 4, Step 1. The residue was chromatographed on a silica gel column to provide 3.40 g (81% yield) t-butyl 4-(2-bromo-4-(trifluoromethyl)phenoxy)piperidine- 1 -carboxylate as a white solid. LCMS (ESI, m/z): 424 [M+H].j003201 A flask was charged with t-butyl 4-aminopiperidine-1-carboxylate (416 mg, 2.06 mmol, 2.00 equiv),

Used as medicine and pesticide intermediate

Molecular Weight:243.00
XLogP3:3.6
Hydrogen Bond Acceptor Count:4
Exact Mass:241.93543
Monoisotopic Mass:241.93543
Heavy Atom Count:12
Complexity:156
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes