Silver(i) polymeric coordination frameworks assembled with the new multimodal ligand 2,2′-azobispyrazine
作者:Lucia Carlucci、Gianfranco Ciani、Davide M. Proserpio、Silvia Rizzato
DOI:10.1039/b209580g
日期:2003.2.27
The synthesis of the new polyfunctional ligand 2,2â²-azobispyrazine (azpyz), able to bind up to four different metal centres, and the self-assembly of polymeric coordination networks from different Ag(I) salts have been carried out. Four different structural types of polymeric species have been characterized: [Ag(azpyz)2]ClO4
(1a) and [Ag(azpyz)2]BF4(1b) contain 1D helical chains, [Ag(azpyz)2]SbF6·0.5CH2Cl2
(2) is comprised of undulating 2D layers of (4,4)-topology, [Ag2(azpyz)(H2O)](BF4)2
(3) consists of 2D sheets, containing μ4-η6-azpyz ligands, with two distinct types of metal centres, and [Ag4(azpyz)3](ClO4)4
(4) is a complex 3D network, exhibiting μ4-η6-azpyz and μ4-η5-azpyz ligands, with four different types of Ag centres. In these compounds the azpyz ligands show varied bonding modes, using from 2 up to all 6 of its N-donor atoms. Most of the silver metal centres exhibit high coordination numbers (up to 5 and 6).
我们合成了新的多官能配体 2,2â²-偶氮二吡嗪(azpyz),这种配体能够结合多达四种不同的金属中心,我们还利用不同的 Ag(I)盐进行了聚合物配位网络的自组装。研究表征了四种不同结构类型的聚合物:[Ag(azpyz)2]ClO4(1a)和[Ag(azpyz)2]BF4(1b)含有一维螺旋链,[Ag(azpyz)2]SbF6Â-0.5CH2Cl2 (2) 由 (4,4) 拓扑起伏的二维层组成,[Ag2(azpyz)(H2O)](BF4)2 (3) 由二维片组成,含有δ4-δ-6-azpyz 配体、Ag4(azpyz)3](ClO4)4(4)是一个复杂的三维网络,含有δ4-δ-6-azpyz 和δ4-δ-5-azpyz 配体,以及四种不同类型的银中心。在这些化合物中,azpyz 配体显示出不同的成键模式,使用了 2 个到全部 6 个 N-供体原子。大多数银金属中心的配位数都很高(高达 5 和 6)。