Molecular squares, coordination polymers and mononuclear complexes supported by 2,4-dipyrazolyl-6H-1,3,5-triazine and 4,6-dipyrazolylpyrimidine ligands.
Molecular squares, coordination polymers and mononuclear complexes supported by 2,4-dipyrazolyl-6H-1,3,5-triazine and 4,6-dipyrazolylpyrimidine ligands.
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DOI：
10.1039/c9dt04003j
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发表时间：
2019-11
影响因子：
4
通讯作者：
Izar Capel Berdiell;Sarah E. Farmiloe;Rafal Kulmaczewski;M. Halcrow
中科院分区：
文献类型：
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作者：
Izar Capel Berdiell;Sarah E. Farmiloe;Rafal Kulmaczewski;M. Halcrow
2，4-二(吡唑-1-基)-6H-1，3，5-三嗪(L1)的Fe[BF4]2是一个高自旋分子方块，[{Fe(L1)}4(μ-L1)4][BF4]8，其晶体中还含有罕见的HPzBF3(HPz=吡唑)加合物。另外三个具有不同吡唑取代基(L2-L4)的2，4-二(吡唑-1-基)-6H-1，3，5-三嗪衍生物在第一排过渡离子存在下不稳定，但与银(I)形成单核、聚合物或分子方形配合物。大多数这些化合物都涉及双双齿双(吡唑基)三嗪配位，这在这类配体中是不常见的，分子方块通过阴离子π、AgX和/或C-HX(X=O或F)的组合封装了一个或两个BF4-、ClO4-或SbF6-离子。用4，6-二(吡唑-1-基)-2H-嘧啶(L5)或其2-甲基和2-氨基衍生物(L6和L7)与Fe[NCS]2或Fe[NCSe]2反应，得到单核[Fe(NCe)2L2]和/或一维配位聚合物Catena-[Fe(NCe)2(μ-L)](E=S或Se，L=L5-L7)。同构体[Fe(NCS)2L2]和[Fe(NCSE)2L2]的醇溶液表现出不同的分子间氢键模式，反映了阴离子配体的受体性质。这些铁化合物都是高自旋的，尽管[Fe(NCSE)2(L5)2]的退火溶剂化晶体提供了一个突然的、低温自旋转变的新相。Catena-[Fe(H2O)2(μ-L5)][ClO4]2是一种顺铁和反铁中心交替的配位聚合物。
The Fe[BF4]2 complex of 2,4-di(pyrazol-1-yl)-6H-1,3,5-triazine (L1) is a high-spin molecular square, [{Fe(L1)}4(μ-L1)4][BF4]8, whose crystals also contain the unusual HPzBF3 (HPz = pyrazole) adduct. Three other 2,4-di(pyrazol-1-yl)-6H-1,3,5-triazine derivatives with different pyrazole substituents (L2-L4) are unstable in the presence of first row transition ions, but form mononuclear, polymeric or molecular square complexes with silver(i). Most of these compounds involve bis-bidentate di(pyrazolyl)triazine coordination, which is unusual for that class of ligand, and the molecular squares encapsulate one or two BF4-, ClO4- or SbF6- ions through combinations of anionπ, AgX and/or C-HX (X = O or F) interactions. Treatment of Fe[NCS]2 or Fe[NCSe]2 with 4,6-di(pyrazol-1-yl)-2H-pyrimidine (L5) or its 2-methyl and 2-amino derivatives (L6 and L7) yields mononuclear [Fe(NCE)2L2] and/or the 1D coordination polymers catena-[Fe(NCE)2(μ-L)] (E = S or Se, L = L5-L7). Alcohol solvates of isomorphous [Fe(NCS)2L2] and [Fe(NCSe)2L2] compounds show different patterns of intermolecular hydrogen bonding, reflecting the acceptor properties of the anion ligands. These iron compounds are all high-spin, although annealing solvated crystals of [Fe(NCSe)2(L5)2] affords a new phase exhibiting an abrupt, low-temperature spin transition. Catena-[Fe(H2O)2(μ-L5)][ClO4]2 is a coordination polymer of alternating cis and trans iron centres.