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331.
Aragoni MC Arca M Bencini A Blake AJ Caltagirone C Danesi A Devillanova FA Garau A Gelbrich T Isaia F Lippolis V Hursthouse MB Valtancoli B Wilson C 《Inorganic chemistry》2007,46(19):8088-8097
Two new ligands 7-anthracenylmethyl-13-methylpyridyl-1,4,10-trioxa-7,13-diazacyclopentadecane (L4) and 7-anthracenylmethyl-13-(2,2-dimethyl-2-hydroxyethyl)-1,4,10-trioxa-7,13-diazacyclopentadecane (L(5)) have been synthesized and characterized. Both derive from 7-anthracenylmethyl-1,4,10-trioxa-7,13-diazacyclopentadecane (L(3)) and differ for having a differently functionalized pendant arm covalently attached to the remaining secondary nitrogen donor of the macrocyclic framework. The protonation and coordination behavior of L(4), L(5), and the unbranched L(3) with metal ions have been studied in MeCN/H2O (1:1 v/v, 298.1 K, I = 0.1 M) using potentiometric methods. The crystal structures of L(3), [(H2L(3))(HL(3))](ClO4)3, and the complex [CdL(3)(NO3)2] have been determined by single-crystal X-ray methods. The fluorescent behavior of L(3)-L(5) in the presence of Cu(II), Zn(II), Cd(II), Hg(II), and Pb(II) has been studied as a function of pH in MeCN/H2O (1:1 v/v). The presence of Cu(II), Hg(II), or Pb(II) does not affect the fluorescent behavior observed for the three free ligands upon changing the pH. Interestingly, the fluorescent emission of L(3) and L(5) is selectively enhanced only in the presence of Cd(II) at basic pH. The same effect is observed for L4 in the presence of Cd(II) or Zn(II) at about pH 7. 相似文献
332.
Michael A. Beckett Catherine C. Bland Michael B. Hursthouse 《Journal of organometallic chemistry》2007,692(13):2832-2838
The solid-state structures of two non-metal pentaborates [Me3NCH2CH2OH][B5O6(OH)4] (1) and [4-MepyH, 4-Mepy][B5O6(OH)4] (2) have been determined by single-crystal X-ray diffraction methods. Structures 1 and 2 both contain supramolecular pentaborate frameworks held together by extensive H-bond interactions. The framework of 1 exists essentially as planes of pentaborate anions linked via three pairwise ‘planar’ β → α interactions, with a fourth β → β interaction crosslinking the planes. The framework of 2 is very similar except that one of the three pairwise linkages within the plane is replaced by pairwise ‘step-like’ bifurcated H-bonds to both α sites of a neighboring anion. The cations in 1 and the cations and neutral 4-Mepy ligands in 2 are present in the framework cavities and channels, with additional H-bond interactions existing between cations and anions. 相似文献
333.
在全密闭植物工厂中水培种植中药蒲公英,以发射不同波段光谱的荧光灯及LED灯作为药材生长光源,并结合ICP–AES技术分析了不同光谱条件对蒲公英无机元素吸收和积累的影响。结果表明:(1)相近的光合有效辐射(PAR)条件下,单一红光R及混合光FLRB有利于水培蒲公英可食生物量的积累,单一蓝光B处理下可食生物量最低;(2)荧光灯FL条件下蒲公英地上部分常量无机元素含量比值为K∶Ca∶P∶Mg∶Na=79.74∶32.39∶24.32∶10.55∶1.00,微量无机元素含量比值为Fe∶Mn∶B∶Zn∶Cu=9.28∶9.71∶3.82∶2.08∶1.00;(3)峰值为660nm的红光有利于蒲公英对Ca,Fe,Mn,Zn元素的吸收,Cu元素含量受光谱条件的影响不明显;(4)蒲公英地上部分对Ca,Na,Mn,Zn四种元素的积累量均在纯红光R下最高,而对其余六种元素的积累量以混合光FLRB条件下最高。 相似文献
334.
Reaction of cobalt hydroxide with the α,ω-dicarboxylic acid and 1,12-dodecanedioic acid under ambient conditions results in the formation of a trihydrate Co(C12H20O4)(H2O)3 (1). Single crystal X-ray diffraction studies show 1 to crystallise in the orthorhombic space group Pccn with cell parameters a = 40.2343(7) Å, b = 8.1519(1) Å, c = 9.1011(2) Å. The structure has a very pronounced two dimensional character, with a separation of hydrophobic n-alkyl chains from the carboxylate groups, the Co2+ cations and the water of crystallisation. The structure is discussed in respect of the structures of other known compositionally related compounds, including the dihydrate Co(C12H20O4)(H2O)2. 相似文献
335.
Pawan K. Khanna Christopher P. Morley Michael B. Hursthouse K. M. Abdul Malik Oliver W. Howarth 《Heteroatom Chemistry》1995,6(6):519-524
Treatment of tetrakis(triphenylphosphine)platinum with elemental selenium (red or vitreous) in toluene solution under reflux yields an insoluble solid. This dissolves in dichloromethane with reaction, eventually to form a 1 : 1 mixture of [PtCl2(PPh3)2] and the new compound [Pt(Se2CH2)(PPh3)2], which has been characterized by multinuclear NMR spectroscopy and X-ray crystallography. Under the same conditions, tetrakis(triphenylphosphine)-palladium yields only decomposition products. © John Wiley & Sons, Inc. 相似文献
336.