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Chemical Products 1-Bromo-2,5-difluorobenzene Production Methods<br>General procedure: A FEP or PFA reactor equipped with a Teflon-lined magnetic stir bar and connected to a gas-washing bottle was charged with substituted benzene (0.95u20131.10 mmol), 1, 1, 1, 3, 3-pentafluorobutane (1u20132 mL per mmol of C6H5R), and BF3 u00b7 Et2O (1.3u20131.5 mmol per mmol of C6H5R). The mixture was stirred for 10u201315 min at 0u20135u00b0C (ice bath), and XeF2 (1.2u20131.3 mmol per mmol of C6H5R) was added in portions. After addition of each portion, the mixture was stirred for 3u20135 min at 22u201325u00b0C and cooled again. When the addition was complete the dark solution was stirred for 15u201330 min at 22u201325u00b0C, 10percent aqueous KHCO3 was added, and the upper organic layer was separated, passed through a short column charged with silica gel (40u201360 u03bcm), and dried over MgSO4. The solution was analyzed by 19F NMR and GC/MS. The main products are given in table, and the others are listed below (GC/MS data).
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Chemical Products 1-Bromo-2,5-difluorobenzene Description CLEAR COLOURLESS LIQUID Chemical Products 1-Bromo-2,5-difluorobenzene Basic Attributes CAS No：399-94-0 Molecular Formula ：C6H3BrF2 Molecular Mass ：192.99 Exact Mass ：191.938614 PSA ：0 A^2 LogP ：3 EINECS ：206-920-0 InChIKeys ：XCRCSPKQEDMVBO-UHFFFAOYSA-N H-bond Acceptor ：2 H-bond Donor ：0 SP3 ：0.00 RBN ：0 Chemical Products 1-Bromo-2,5-difluorobenzene Characteristics Density ：1.7±0.1 g/cm3 Melting Point ：−31 °C(lit.) Bolling Point ：58-59 °C20 mm Hg(lit.) Flash Point ：149 °F Refractive Index ：1.507 Solubility ：H2O: Insoluble BRN ：1680893 Chemical Products 1-Bromo-2,5-difluorobenzene Safety Information
Hazard Class ：IRRITANT, FLAMMABLE HS Code ：29039990 UN No. ：UN2922 WGK_Germany ：3 Risk Code ：36/37/38 Safety Instructions ：26-36/37/39-2637/39-37/39 Dangerous Mark ：Xi,F,Xn P Code ：P261-P305 + P351 + P338 Hazard Statements ：H315-H319-H335 Hazard Note ：Flammable Chemical Products 1-Bromo-2,5-difluorobenzene Product Usage Used as medicine, pesticide, liquid crystal material intermediate Chemical Products 1-Bromo-2,5-difluorobenzene Production Methods General procedure: A FEP or PFA reactor equipped with a Teflon-lined magnetic stir bar and connected to a gas-washing bottle was charged with substituted benzene (0.95–1.10 mmol), 1, 1, 1, 3, 3-pentafluorobutane (1–2 mL per mmol of C6H5R), and BF3 · Et2O (1.3–1.5 mmol per mmol of C6H5R). The mixture was stirred for 10–15 min at 0–5°C (ice bath), and XeF2 (1.2–
1.3 mmol per mmol of C6H5R) was added in portions. After addition of each portion, the mixture was stirred for 3–5 min at 22–25°C and cooled again. When the addition was complete the dark solution was stirred for 15–30 min at 22–25°C, 10percent aqueous KHCO3 was added, and the upper organic layer was separated, passed through a short column charged with silica gel (40–60 μm), and dried over MgSO4. The solution was analyzed by 19F NMR and GC/MS. The main products are given in table, and the others are listed below (GC/MS data).
