94-25-7Relevant articles and documents
Biorenewable carbon-supported Ru catalyst for: N -alkylation of amines with alcohols and selective hydrogenation of nitroarenes
Goyal, Vishakha,Narani, Anand,Natte, Kishore,Poddar, Mukesh Kumar,Ray, Anjan,Sarki, Naina,Tripathi, Deependra
, p. 14687 - 14694 (2021/08/23)
Herein, we developed a renewable carbon-supported Ru catalyst (Ru/PNC-700), which was facilely prepared via simple impregnation followed by the pyrolysis process. The prepared Ru/PNC-700 catalyst demonstrated remarkable catalytic activity in terms of conversion and selectivity towards N-alkylation of anilines with benzyl alcohol and chemoselective hydrogenation of aromatic nitro compounds. In addition, local anesthetic pharmaceutical agents (e.g., butamben and benzocaine), including key drug intermediates, were synthesized in excellent yields under mild conditions and in the presence of water as a green solvent. Moreover, the prepared Ru/PNC-700 catalyst could be easily recovered and reused up to five times without any apparent loss in activity and selectivity.
Pd/C-catalyzed transfer hydrogenation of aromatic nitro compounds using methanol as a hydrogen source
Goyal, Vishakha,Sarki, Naina,Natte, Kishore,Ray, Anjan
, (2021/06/28)
We describe the selective transfer hydrogenation of aromatic nitro compounds to anilines using Pd/C as a heterogeneous catalyst with methanol as a green reductant. Nitroarenes bearing both electron-releasing and electron-deficient groups are amenable to this method and enable the synthesis of corresponding arylamines in moderate to good selectivities including the synthesis of butamben, a local anesthictic drug molecule. This new concise protocol is simple, ligand-free and does not require the supply of external molecular hydrogen.
Method for preparing p-aminobenzoic acid alkyl ester
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, (2019/10/29)
The invention discloses a method for preparing p-aminobenzoic acid alkyl ester. The method comprises the following steps: performing an esterification reaction on p-nitrobenzoic acid and a corresponding alkyl alcohol so as to obtain p-nitrobenzoic acid alkyl ester, and further performing catalytic hydrogenation, so as to obtain the p-aminobenzoic acid alkyl ester, wherein the solvent used in the esterification reaction is p-nitrobenzoic acid alkyl ester; the mole ratio of p-nitrobenzoic acid to the p-nitrobenzoic acid alkyl ester is (1:0.5)-(1:1); the alkyl alcohol is a C4-C8 alcohol; the moleratio of the p-nitrobenzoic acid to the alkyl alcohol is (1:0.98)-(1:1.1); the esterification reaction is implemented in the presence of the catalyst; and the catalyst is sulfuric acid or p-toluenesulfonic acid. The invention unexpectedly shows that an esterification reaction product, namely the p-aminobenzoic acid alkyl ester, can be used as a solvent of the esterification reaction, with the esterification reaction solvent, the process that an alcohol or benzene solvent needs to be recycled in a conventional method is avoided, not only is aftertreatment simple, but also solvent consumption is avoided, and the method is environment-friendly.