Three novel, non-symmetrical bis(aminoalkyl)phosphinic acids, L¹–L³, have been synthesized and characterized. Solution studies on the coordination abilities of the ligands have shown that these compounds form various protonated mono- and bis-complexes, where copper(II) coordination is realized through the nitrogen atom(s) of the amino group(s), supported by oxygen(s) from the phosphinate unit(s). Potentiometric titrations and a full spectroscopic analysis clarified the species distribution profiles and detailed coordination modes. The results show that L¹–L³ ligands are efficient chelating agents for Cu(II) ions; their metal binding abilities were compared to structurally related compounds described earlier in the literature.

中文翻译：

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非对称双（氨基烷基）次膦酸酯：具有增强的Cu（ii）离子结合力的新配体†

合成并表征了三种新型的非对称双（氨基烷基）次膦酸L ¹ –L ³。对配体配位能力的溶液研究表明，这些化合物形成各种质子化的单和双配合物，其中铜（II）配位是通过氧所支持的氨基的氮原子实现的。来自次膦酸酯单元。电位滴定和全光谱分析阐明了物种分布图和详细的配位模式。结果表明，L ¹ –L ³配体是Cu（II）的有效螯合剂。）离子; 将它们的金属结合能力与文献先前所述的结构相关化合物进行了比较。