The first bis-cyanoxime: synthesis and properties of a new versatile and accessible polydentate bifunctional building block for coordination and supramolecular chemistry
作者:Carl Cheadle、Nikolay Gerasimchuk、Charles L. Barnes、Sergiy I. Tyukhtenko、Svitlana Silchenko
DOI:10.1039/c2dt31924a
日期:——
N′-(2-cyano-2-oximinoacetyl)piperazine (HL, 2) using a room temperature nitrosation reaction with gaseous methylnitrite. Synthesized bis-cyanoxime was characterized by 1H, 13C NMR, UV-visible, IR spectroscopy and the X-ray analysis. The ligand 2 exists as a mixture of three diastereomers arising from the syn- and anti-geometry of the cyanoxime group. The prolonged crystallization of 2 from an ethanol–water mixture leads
使用在环境条件下进行的两步操作,高收率合成了一种新的多齿双功能有机配体-Di- N,N '-(2-氰基-2-氧亚氨基乙酰基)哌嗪。首先,哌嗪以及纯净的甲基氰基乙酸酯生成二-N,N '-(氰基乙酰基)哌嗪(1),然后将其转化为双氰基肟,二-N,N '-(2-氰基-2-氧亚氨基乙酰基)哌嗪(HL,2)使用室温下与气体进行亚硝化反应亚硝酸盐。合成的双氰基肟的特征在于1 H,13 C NMR,紫外可见光,IR光谱和X射线分析。配体2作为三种非对映异构体的混合物存在,这是由氰肟基的顺式和反式构型产生的。从乙醇-水混合物中长时间结晶2会导致形成:(a)无色晶体,根据X射线分析,它们包含51.2:48.8%的具有相同H键的两种异构体共结晶混合物(少数),以及(b)白色无定形物质,代表几乎纯的反异构体(多数)。2的质子化导致形成黄色二价阴离子,在亚硝基生色团中其n→π*跃迁表现出明显的溶剂化变色现象。使用NaOC