2-Bromo-4-nitrobenzenamine

Yellow solid

At room temperature a solution of 4-nitroaniline (1.60 g, 11.6mmol, 1 equiv.) in DCM (40 mL) and MeOH (20 mL) was treated with PHT (6.30 g, 12.7mmol, 1.1 equiv.) in a portion-wise manner. Stirring was then continued for 0.5 h. The mixture was diluted with Et2O (50 mL) and washed first with a saturated aqueous solution of Na2S2O3 (40 mL) and then brine (40 mL). The organic extract was dried over MgSO4 before filtration and solvent removal under reduced pressure. Purification by flash columnchromatography (c-Hex-EtOAc; 2:1) gave S8 (2.50 g, 99percent) as a yellow solid.General procedure: To a mixture of anilines or phenols (0.7 mmol) the brominatingagent (1) (0.72 g, 0.7 mmol) in dichloromethane(30 ml)-methanol (15 ml) was added. The reactionmixture was stirred at room temperature until decolorizationof the orange solution took place. The progress of thereaction was monitored by TLC (eluent: n-hexane/ethylacetate, 7:3). After completion of the reaction, the solventwas evaporated and diethyl ether (10 ml) was added to theresidue. The supernatant was decanted and the insolubleresidue was washed by ether (3 × 10 ml). The combinedether extracts were dried on magnesium sulfate and also evaporated under vacuum to afford monobromo anilines ormonobromo phenols which was purified by flash columnchromatography over silica gel (n-hexane/ethyl acetate, 7:3).276 mg (2 mmol) of p-nitroaniline and 143 mg (1.2 mmol) of potassium bromide were added to a 50 ml three-necked flask Add AcOH: H2O = 9: 1 10ml solvent, transferred to constant temperature magnetic stirring water bath, control the temperature of 30 stirring anti- 1.8 g (1.8 mmol) of ZnAl-BrO3 - LDHs were added slowly in portions over a period of 1 hour before the reaction. After the reaction, The reaction solution was extracted with methylene chloride and the combined organic phases were added to a dichloromethane phase by adding two syrups of silica gel (200-300), And the dichloromethane was distilled off under reduced pressure, and the residue was purified by column chromatography (petroleum ether: ethyl acetate = 10: 1 as eluent)Separation gave 399 mg of pure product. The material was a yellow solid in 92percent yield.A solution of 4-nitroaniline (10 g, 72 mmol) in DMF (150 mL) as added NBS (12.9 g, 72 mmol) portionwise and the mixture was stirred for 30 min at the same temperature. Then the ice-bath was removed and the stirring was continued at rt overnight (18 h). The mixture was poured into water (500 mL) and filtered, the orange solid was washed with water (50 mL × 2) and recrystallized from EtOH to affordpale-yellow crystals (14.3 g, 92 percent); Rf = 0.21 (PE : EtOAc = 5 : 1); m.p. 98 -100 °C; 1H-NMR (CDCl3, 300 MHz) δ: 8.37 (d, J = 2.1 Hz, 1H), 8.03 (dd, J = 2.4 Hz, J = 2.7 Hz, 1H), 6.74 (d, J = 9.0 Hz, 1H), 4.48 (br, 2H).General procedure: To a magnetic solution of aromatic compound (1 mmol)in acetonitrile (5 mL), OXBTEATB (0.233 g, 0.5 mmol) wasadded and stirred at room temperature for the appropriatetime (Table 1). The reaction was monitored by TLC (eluent:n-hexane/ethyl acetate: 5/1). The reaction mixture was transferredinto a separatory funnel after filtration of OXBTEABand was extracted with water (15 mL) and dichloromethane(20 mL). The organic layer was dried over anhydrousNa2SO4, and the solvent was concentrated in a rotary evaporator.The crude product was purified by passing it over acolumn of silica gel using a mixture of n-hexane and ethylacetate as the eluent. In order to regenerate the reagent, whitesolid was treated with liquid bromine. All the product structureswere confirmed by comparison of melting point or 1HNMR spectra with ones reported in the literature [29a-29e].General procedure: To a round bottom flask was added 5 mmol of acetophenone, 0.5 mmol of 2-methylpyridine nitrate and 5.5 mmol of 40 wtpercent HBr, 60 ° C under the open flask stir reaction 6h, The yield of α-bromoacetophenone was 95percent The product was isolated by silica gel column chromatography (ethyl acetate / boiling point 60-90 ° C petroleum ether) at 200-300 mesh, The isolated yield was 88percent.Bromine (2.05 mL, 40 mmol) was added dropwise to a solution of 4-nitroaniline(5.0 g, 36 mmol) in acetic acid (150 mL) at room temperature under an inert atmosphere of argon. The resulting reaction mixture was stirred at room temperature for 2 h. It was then quenched with dilute aqueous NaPreparation of 2-bromo-4-nitroaniline:Bromine (2.05 mL, 40 mmol) was added dropwise to a solution of 4- nitroaniline (5.0 g, 36 mmol) in acetic acid (150 mL) at rt under an inert atmosphere of argon. The resulting reaction mixture was stirred at room temperature for 2 h. It was then quenched with dilute aqueous Na2-Bromo-4-nitroanilineTo a solution of 4-nitro-phenylamine (50 g, 0.36 mol) in AcOH (500 mL) was added BrExample 33 2-Cyclopropyl-1H-indol-5-amine 2-Bromo-4-nitroaniline To a solution of 4-nitro-aniline (25 g, 0.18 mol) in HOAc (150 mL) was added liquid Br2-Bromo-4-nitroanilineEXAMPLE I

Molecular Weight:217.02
XLogP3:2.3
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:3
Exact Mass:215.95344
Monoisotopic Mass:215.95344
Topological Polar Surface Area:71.8
Heavy Atom Count:11
Complexity:159
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes