The palladium-on-carbon (Pd/C)-catalyzed hydrogenative deprotection of the N-benzyl-protecting group was effectively facilitated by the combined use of niobic acid-on-carbon (Nb2O5/C). Nb2O5/C is an acidic heterogeneous catalyst prepared from NbCl5 and activated carbon. The catalysts were easily removed from the reaction mixture and reusable. Deprotected amines were obtained in excellent yields without an additional neutralization process. The facilitating effect of Nb2O5/C was also observed during the Pd/C-catalyzed hydrogenative deprotection of the N-benzyloxycarbonyl (Cbz) and O-benzyl groups.

中文翻译：

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使用钯和碳上铌酸的混合催化剂对N-苄基进行便捷的加氢脱保护

碳铌酸（Nb2O5 / C）的联合使用有效地促进了碳钯（Pd / C）催化的N-苄基保护基的氢化脱保护。Nb2O5 / C是由NbCl5和活性炭制备的酸性多相催化剂。催化剂很容易从反应混合物中除去并可以重复使用。在没有额外的中和过程的情况下，以优异的产率获得了脱保护的胺。在Pd / C催化的N-苄氧羰基（Cbz）和O-苄基的氢化脱保护过程中，也观察到Nb2O5 / C的促进作用。