Structural characterization of an enantiopure hydroxo-bridged binuclear iron(III) complex with empty one-dimensional helical channels
Structural characterization of an enantiopure hydroxo-bridged binuclear iron(III) complex with empty one-dimensional helical channels
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DOI：
10.1021/ic049145n
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发表时间：
2005-03-07
影响因子：
4.6
通讯作者：
Ray, M
中科院分区：
文献类型：
--
作者：
Alam, MA;Nethaji, M;Ray, M
具有氢键能力的手性四齿配体、Fe3+和醋酸离子组装成羟基桥接的双核配合物，其分子式为[Fe-2(III)(mu-OH)(mu-OAc)(S-L)(2)]。4H(2)O(1)其中H2S-L = S-2-（2-羟基苄基氨基）-3（1h -咪唑-4-酰基）-丙酸。晶体1含有直径7.3-9.8埃的右旋一维螺旋通道。与具有相反手性的配体的类似反应形成具有左旋螺旋通道的配合物（1a）。在95℃下加热1的晶体，在减压下选择性地从通道中除去三种水，形成具有空通道的对不纯多孔晶体（溶剂可达空隙率为18% v/v）。分子间的氢键在咪唑N-H和1-2的酚酸氧之间形成一个带有桥接羟基的C-6对称螺旋，基团指向通道内部。配体中所有能形成氢键的原子与一个水分子在整个晶体中形成一个扩展的氢键网络。将2的空通道暴露在碘蒸气中表明这些通道被碘部分填充。1.4H(2)O的晶体数据包括：六边形，P6(1), a = b = 13.164(3)埃，c = 36.305（11）埃，alpha = beta = 90度，gamma = 120度，Z = 6, R1 = 0.0387, wR2 = 0.0842。1.2H(2)O的晶体数据包括：六边形，P6(5), a = b = 13.151(4)埃，c = 36.558(2)埃，alpha = beta = 90度，gamma = 120度，Z = 6, R1 = 0.0416, wR2 = 0.1190。晶体数据为2。H2O包括如下：六边形，P6(1), a = b = 13.160(7)埃，c 36.559 (4) α, β = 90度，120度，Z = 6, R1 0.0574, wR2 = 0.1423。
A H-bond capable chiral tetradentate ligand, Fe3+, and acetate ion assembles into a hydroxo-bridged binuclear complex with the formula [Fe-2(III)(mu-OH)(mu-OAc)(S-L)(2)].4H(2)O (1) where H2S-L = S-2-(2-hydroxy-benzylamino)-3(1H-imidazol-4-yl)-propionic acid. The crystal of 1 contains right-handed one-dimensional (M) helical channels with 7.3-9.8 Angstrom diameter. A similar reaction with a ligand having opposite chirality forms the complex with left-handed helical channels (1a). Heating the crystals of 1 at 95 degreesC under reduced pressure selectively removes three waters from the channel forming an enantiopure porous crystal with empty channels (solvent accessible voids 18% v/v). Intermolecular hydrogen bonding between the imidazole N-H and phenolate oxygen in 1-2 forms a C-6 symmetric helix with bridging hydroxo, groups pointing inside the channels. All the H-bond capable atoms in the ligand along with one water molecule form an extended H-bonded network throughout the crystal. Exposing the empty channels of 2 to iodine vapor indicates partial filling of the channels with iodine. Crystal data for 1.4H(2)O include the following: hexagonal, P6(1), a = b = 13.164(3) Angstrom, c = 36.305 (11) Angstrom, alpha = beta = 90degrees, gamma = 120degrees, Z = 6, R1 = 0.0387, wR2 = 0.0842. Crystal data for 1.2H(2)O include the following: hexagonal, P6(5), a = b = 13.151(4) Angstrom, c = 36.558(2) Angstrom, alpha = beta = 90degrees, gamma = 120degrees, Z = 6, R1 = 0.0416, wR2 = 0.1190. Crystal data for 2.H2O include the following: hexagonal, P6(1), a = b = 13.160(7) Angstrom, c 36.559 (4) alpha, beta = 90degrees, 120degrees, Z = 6, R1 0.0574, wR2 = 0.1423.