Gerasimchuk Nikolay
Missouri State University, Department of Chemistry, Temple Hall 456, Springfield, MO 65897, USA.
Dalton Trans. 2019 Jun 11;48(23):7985-8013. doi: 10.1039/c9dt01057b.
During the past three decades, considerable research effort has been dedicated to a new class of organic ligands - cyanoximes - which have the general formula NC-C([double bond, length as m-dash]NOH)-R, where R is an electron-withdrawing group. The presence of the CN group makes cyanoximes ∼10 000 times more acidic and better ligands than other known conventional monoximes and dioximes. Also, in numerous cases, this group provides extra nitrogen donor atoms to support the formation of bridges between metal centres in the obtained coordination polymers. With 36 different R groups, the most abundant is the family of mono-cyanoximes, followed by 7 bis-cyanoximes which include aromatic and aliphatic spacers and, lately, tris-cyanoxime representing a 'tripod'. The total number of obtained and characterized compounds is 44. These simple, low molecular weight molecules represent a series of new excellent ampolydentate ligands - 'molecular Lego', or building blocks - for coordination and organometallic chemistry. Uncomplexed ligands, their alkali metal salts, and metal complexes show a large spectrum of biological activity, ranging from growth regulation in plants and antimicrobial activity, to significant in vitro and in vivo cytotoxicity against human cancers. Currently, there are more than three hundred cyanoxime-based complexes, synthesized and studied using a variety of different spectroscopic methods and X-ray analysis. In this review, the preparation and stereochemistry of cyanoxime ligands, their structures and properties, and the most interesting coordination compounds with a broad spectrum of practical applications are summarized.
在过去三十年中，大量的研究工作致力于一类新型有机配体——氰肟，其通式为NC-C(=NOH)-R，其中R是吸电子基团。氰基的存在使氰肟比其他已知的传统单肟和二肟酸性强约10000倍，且是更好的配体。此外，在许多情况下，该基团提供额外的氮供体原子，以支持所得配位聚合物中金属中心之间桥键的形成。有36种不同的R基团，最丰富的是单氰肟家族，其次是7种双氰肟，包括芳香族和脂肪族间隔基，最近还有代表“三脚架”的三氰肟。已获得并表征的化合物总数为44种。这些简单的低分子量分子代表了一系列新型的优秀多齿配体——“分子乐高”或构建模块——用于配位化学和有机金属化学。未络合的配体、它们的碱金属盐以及金属配合物表现出广泛的生物活性，从植物生长调节和抗菌活性到对人类癌症显著的体外和体内细胞毒性。目前，使用各种不同的光谱方法和X射线分析合成并研究了三百多种基于氰肟的配合物。在这篇综述中，总结了氰肟配体的制备和立体化学、它们的结构和性质，以及具有广泛实际应用的最有趣的配位化合物。
