Synthesis of a New Series of N,N’-Dimethyltetrahydrosalen (H2 [H2Me]salen) Ligands by the Reductive Ring-Opening of 3,3'-Ethylene-bis(3,4-dihydro-6-substituted-2H-1,3-benzoxazines)
作者:Augusto Rivera、Jicli José Rojas、Jairo Salazar-Barrios、Mauricio Maldonado、Jaime Ríos-Motta
DOI:10.3390/molecules15064102
日期:——
A new series of N,N'-bis(2'-hydroxy-5'-substituted-benzyl)-N,N´-dimethylethane-1,2-diamines (N,N'-dimethyltetrahydrosalen) ligands were prepared in good yield by reduction of the respective 3,3'-ethylene-bis(3,4-dihydro-6-substituted-2H-1,3-benzoxazine) precursors with sodium borohydride . The ligands were characterized by IR, NMR, and elemental analysis, which showed the compounds to be consistent with the proposed structures. Ring-opening reactions of bis-1,3-benzoxazines in the presence of sodium borohydride to produce N,N’-dimethylated tetrahydrosalens (H2 [H2Me]salen) have not been reported in the literature.
通过用硼氢化钠还原相应的 3,3'-乙烯-双(3,4-二氢-6-取代-2H-1,3-苯并恶嗪)前体,制备了一系列新的 N,N'-双(2'-羟基-5'-取代-苄基)-N,N´-二甲基乙烷-1,2-二胺(N,N'-二甲基四氢柳烯)配体,收率良好。通过红外光谱、核磁共振和元素分析对配体进行了表征,结果表明这些化合物与所提出的结构一致。双-1,3-苯并噁嗪在硼氢化钠存在下发生开环反应生成 N,N'-二甲基四氢柳氮烷(H2 [H2Me]salen)的文献尚未见报道。