4-Cyano-2-nitrophenol

yellow powder

General procedure: To a solution of an aromatic aldehyde 1 (0.500 mmol, 1.0 equiv) and TMSN3 (115 mg, 1.00 mmol, 2.0 equiv) in a premixed HFIP/ACN mixture (2.0 mL, 1:1) in a nitrogen-flushed two dram vial wasadded triflic acid (TfOH; 17.7 L, 0.200 mmol, 0.40 equiv) (exotherm and brisk effervescence due tonitrogen gas evolution was immediately observed). The vial was capped and the reaction mixture wasallowed to stir at rt for 20–75 min. The reaction mixture was concentrated under nitrogen. The residueobtained was suspended in CH2Cl2/hexanes mixture and loaded on a silica gel in a 5 g samplecartridge. Purification using a normal phase silica flash column on a CombiFlash purification systemafforded a corresponding aromatic nitrile 2 upon concentration of appropriate fractions.11.9 g of p-hydroxybenzonitrile (0.1 mol) and 50 mL glacial acetic acid were added to a 250 mL three-necked flask, added dropwise with the mixture of 8 mL concentrated nitric acid and 12 mL glacial acetic acid. After dripping, the solution was slowly heated to 45-50° C. to react 1.5 hours, tested by TLC, the starting materials were reacted completely; then cooled down, added with dichloromethane, standing, to separate the upper organic layer, and then washed by water, 5percent sodium bicarbonate solution and saturated brine, 50 mL each. Solvent was recovered under reduced pressure to get 15.5 g of light yellow solid 3-nitro-4-hydroxybenzonitrile (VII), with a yield of 94.5percent.Step A:4-Hydroxy-3-nitrobenzonitrile; General procedure: A suspension of 2-methylphenol(18.5 mmol, 1.0 eq) and Cu(NOTo a mixture of HNO3 (2.7mL, 63.Ommol) and AcOH (5mL) was added 4- hydroxybenzonitrile (5g, 42mmol) in AcOH (5mL) dropwise at 40 00. The reaction mixture was heated at 55 00 for 20 mm. The TLC showed reaction to be complete. The reaction mixture was poured into ice-water (lOOmL). The precipitated solid was filtered, washed with water (200mL) and dried under vacuum to afford 4-hydroxy-3- nitrobenzonitrile as a yellow solid. Yield: 2.5g (67percent); 1H NMR (400 MHz, DMSO-d612.34 (bs, 1H), 8.43 (5, 1H), 7.94 (d, J= 10.5 Hz, 1H), 7.24 (d, J= 8.7 Hz, 1H); MS (ESl+) for CHNOS m/z 163.03 [M+H].General procedure: Phenol (10 mmol) and urea nitrate (10 mmol)were mixed together in acetonitrile–water (95:5, 5 ml) in a 25 ml round bottomed flask and placed in a Milestone’s Start SYNTH microwave reactor. The reaction mixture was heated at 80°C for 40–50 min. At the end of the reaction, the reaction mixture was allowed to cool at room temperature, treated with water, and extracted with dichloromethane. After removing the solvent under reduced pressure, the residue was purified by column chromatography on silica gel to give the corresponding nitrophenol. In allcases ortho-nitrophenols were obtained selectively without any evidence forthe formation of the para-substituted nitrophenols. All the compoundsobtained were characterized by 1H NMR, 13C NMR, mp (for solids), GC–MSand in comparison with authentic samples.General procedure: To a solution of N-hydroxysalicylamide (0.5 g, 3.26 mmol) in anhydrous DMF (5 ml) was added 2a or 2b (3.26 mmol) and freshly calcinated K2CO3 (1.35 g, 9.78 mmol) and the mixture was kept, with stirring at the room temperature overnight. DMF was removed in vacuo and the residue was treated with water (10 ml) and then extracted with CH2Cl2 (5 ml). The organic layer was separated, washed with water, dried over anhydrous CaCl2, and purified by flesh chromatography on silica gel using CH2Cl2 as eluent. Dichloromethane was evaporated in vacuo. The resulting residue was benzo[d]oxazol-2(3H)-one 11. The water layer was acidify by hydrochloric acid, filtered and washed with water. The resulting residue was compound 12a(b).

Molecular Weight:164.12
XLogP3:1.6
Hydrogen Bond Donor Count:1
Hydrogen Bond Acceptor Count:4
Exact Mass:164.02219199
Monoisotopic Mass:164.02219199
Topological Polar Surface Area:89.8
Heavy Atom Count:12
Complexity:227
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes