Nitro Reduction

(H2 + Pd/C)







Examples:


Example 1



10% Pd/C (2.50 g, 23.5 mmol) was added under a N2 atmosphere to a chilled (ice bath) solution of the SM (15.0 g, 67.5 mmol) in MeOH (400 mL). The flask was repeatedly evacuated and flushed with H2 gas. The resulting mixture was allowed to warm to RT and left to stir for 72 h under H2. The vessel was subsequently purged with N2 gas. The vessel was chilled (ice bath) and additional 10% Pd/C (2.50 g, 23.5 mmol) was added. The flask was repeatedly evacuated and flushed with H2. The mixture was allowed to warm to RT and stir for 6 h under H2. The vessel was purged with N2 and the crude reaction mixture was filtered through a short plug of celite. The reaction vessel and celite were rinsed with MeOH. The combined filtrates were concentrated in vacuo and the residue was dried under high vac overnight to provide the product as a blackish/grey solid. [12.1 g, 93%]


[Patent Reference: WO2011014535, page 40, (17.3 MB)]



Example 2



The SM (3.31 g, 15.9 mmol) was dissolved in EtOAc (125 mL) and EtOH (125 mL) and passed through the H-Cube at 1 mL/min equipped with a 10% Pd/C catcart (Thales Nano) at full H2 and temperature set at 50 C. The mixture was concentrated in vacuo and the solid dried overnight in a vac oven at 50 C to provide the product. [2.58 g, 91%]


[Patent Reference: WO2012149280, page 65, (4.1 MB)]



Example 3



The SM (2.93 g, 9.18 mmol) was dissolved in EtOAc and treated with 10% Pd/C (970 mg). The reaction mixture was stirred under H2 (1 atm, balloon) overnight. The catalyst was removed by filtration over celite and the filtrate was concentrated in vacuo to provide the product which was used without further purification. [2.30 g, 86%]


[Patent Reference: WO2016012477, page 153, (8.1 MB)]