37% |
With hydrogen;palladium 10% on activated carbon; In ethanol; ethyl acetate; |
B. A mixture of <strong>[129298-23-3]3-hydroxy-2-nitrobenzonitrile</strong> (1.31 g) and 10% Pd/C (131 mg) in ethanol (9 mL) and EtOAc (18mL) was stirred under hydrogen at atmosphere overnight. The catalyst was removed by filtration through Celite and the filtrate was concentrated. The residue was purified by column <n="108"/>(hexanes/EtOAc, 6/4) to give 2-amino-3-hydroxybenzonitrile (398 mg, 37%). |
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With hydrogen;palladium on activated carbon; In ethanol; |
A parr bottle was charged with palladium on activated carbon (5%, 0.196g). A solution of <strong>[129298-23-3]2-nitro-3-hydroxybenzonitrile</strong> (1.31 g, 0.008 mol) in 40 ml of ethanol was added. The reaction mixture was placed under 25 psi of hydrogen gas and shaken for 1 hour. TLC (1:1 hexane:ethyl acetate) shows that no starting material remained. The mixture was filtered through Celite and evaporated to yield 2-amino-3-hydroxybenzonitrile, 1.01 g (0.0075 mol, 94%). 1 H NMR: delta, DMSO 6.00-6.14 (2H, aromatic series of m), 7.15 (1H, d, J 8.5), 10.3 (1H, bs) MS: (EI) m+am/z 134 |
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With methanol; tin(ll) chloride; at 50℃; for 6h; |
To a solution of <strong>[129298-23-3]3-hydroxy-2-nitrobenzonitrile</strong> (1.7 g, 0.01 mol) in MeOH (30 mL) was added SnCl2 (7.9 g, 4.1 mol). The resulting reaction was heated to 50 C and allowed to stir at this temperature for 6 hours. The reaction mixture was then concentrated in vacuo and the resulting residue was taken up in EtOAc. To the resulting solution was added saturated aqueous NaHC03 solution, which caused a white solid to precipitate out of solution. The resulting suspension was filtered through celite and extracted with EtOAc. The organic layer was dried over MgS04, filtered, and concentrated in vacuo to provide 2-amino-3-hydroxybenzonitrile (1.1 g, yield: 79.7%), which was used without further purification. 1H-NMR (CDC13, 400 MHz) delta 6.94 (d, J= 8.4 Hz, 1H), 6.79 (d, J= 8.0 Hz, 1H), 6.53 (t, J= 8.0 Hz, 1H), 5.17 (s, 1H), 4.43 (s, 2H). |