- Electronic absorption and emission properties of bishydrazone [2?×?2] metallosupramolecular grid-type architectures
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Several ditopic ligands containing two tridentate bishydrazone coordination subunits and their Zn(II) and Cd(II) [2 × 2] grid-type complexes were prepared and their photoluminescent properties studied. A special attention was devoted to the influence of the orientation of the hydrazone group N–N[dbnd]in the core of the ligands and their complexes. Its reversal from [pyridine[dbnd]N–N–pyrimidine] (L1) to [pyridine–N–N[dbnd]pyrimidine] (L2) has a strong impact on the observed absorption and emission behaviour of particular ligands (L1 and L2) as well as of their [2 × 2] grid assemblies. The further lateral functionalization of the ligands led to different emission quantum yields of the resulting grids, while their emission and absorption spectra varied very little. The simplest derivative L1 turned out to have the best performance with, for its Zn(II) complex, relatively high quantum yield 60%.
- Holub, Jan,Santoro, Antonio,Lehn, Jean-Marie
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supporting information
p. 223 - 231
(2019/06/07)
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- Tetratopic pyrimidine-hydrazone ligands modified with terminal hydroxymethyl and acryloyl arms and their Pb(ii), Zn(ii), Cu(ii) and Ag(i) complexes
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The first tetratopic pyrimidine-hydrazone (pym-hyz) molecular strands containing terminal hydroxymethyl (L1) and acryloyl (L2) functional groups have been synthesised. L1 was produced by step-wise imine condensation reactions, starting with 6-hydroxymethyl-2-pyridinecarboxaldehyde. L2 was then synthesised through the treatment of L1 with acryloyl chloride. NMR spectroscopy and X-ray crystallography showed that the ligands adopted a helical shape, comprised of 1 and 1/3 helical turns. Both L1 and L2 uncoiled upon reaction with an excess amount of Pb(ii), Zn(ii) and Cu(ii) ions, resulting in linear M 4LA8 complexes (where M = Pb(ii), Zn(ii), or Cu(ii); L = L1 or L2; and A = ClO4-, SO3CF3 - or BF4-). Horse-shoe shaped Pb 2LA4 complexes were also formed by reacting Pb(ii) ions with either L1 or L2 in a 2 : 1 metal to ligand ratio. The addition of Ag(i) ions to either L1 or L2 resulted in Ag2L2A2 double helicates, which were stable in the presence of excess Ag(i). The Pb(ii), Zn(ii) and Ag(i) complexes were characterised by NMR spectroscopy, while UV-Vis spectroscopy was used to probe the Cu(ii) complexes. In addition, X-ray crystallography was used to analyse the linear Pb4L1A8, horse-shoe shaped Pb2L1(ClO4)4, twisted Cu 3L2(SO3CF3)6, and double helicate Ag2L12(SO3CF3)2 complexes yielding the structures [Pb4L1(ClO4)7(H 2O)]ClO4·4CH3NO2 (1), [Pb4L1(SO3CF3)8]2· 6CH3CN·H2O (2), [Pb2L1(ClO 4)2(CH3CN)(H2O)](ClO 4)2·2CH3CN·C4H 10O·H2O (3), [Cu3L2(SO 3CF3)3(CH3CN)2(H 2O)](SO3CF3)3·2CH 3CN·H2O (4) and [Ag2L1 2](SO3CF3)2·CH 3CN·H2O (5), respectively. the Partner Organisations 2014.
- Hutchinson, Daniel J.,Hanton, Lyall R.,Moratti, Stephen C.
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p. 8205 - 8218
(2014/06/09)
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- Generation of [2x2] grid metallosupramolecular architectures from preformed ditopic bis(acylhydrazone) ligands and through component self-assembly
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Ditopic bis(acylhydrazone) ligands, derived from the reactions of carbohydrazides with 2-phenylpyrimidine-4,6-dicarbaldehyde and designed for grid formation with octahedrally coordinating transition-metal ions, exhibit a varied coordination chemistry depe
- Cao, Xiao-Yu,Harrowfield, Jack,Nitschke, Jonathan,Ramirez, Juan,Stadler, Adrian-Mihail,Kyritsakas-Gruber, Nathalie,Madalan, Augustin,Rissanen, Kari,Russo, Luca,Vaughan, Gavin,Lehn, Jean-Marie
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p. 2944 - 2965
(2008/02/10)
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- A diradical bridging ligand with a triplet ground state
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A diradical of nitronyl nitroxide, 2-phenyl-4,6-bis(1′-oxyl-3′ oxido-4′, 4′, 5′, 5′-tetramethyl-4′,5′-dihydro-1′H-imidazole-2′-yl) pyrimidine, was prepared and characterized to have a triplet ground state.
- Oshio, Hiroki,Umeno, Makoto,Fukushi, Toru,Ito, Tasuku
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p. 1065 - 1066
(2007/10/03)
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- STUDIES ON PYRIMIDINE DERIVATIVES. XXII. SITE-SELECTIVE OXIDATION OF DIMETHYLPYRIMIDINES WITH SELENIUM DIOXIDE TO PYRIMIDINE-MONOALDEHYDES
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The oxidation of 2,4-dimethylquinoline and its 1-oxide with an equimolecular amount of selenium dioxide in boiling dioxane afforded 4-methylquinoline-2-carbaldehyde and its 1-oxide, respectively.This oxidation was applicable to the selective preparation o
- Sakamoto, Takao,Sakasai, Takeji,Yamanaka, Hiroshi
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p. 2485 - 2490
(2007/10/02)
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