- Synthesis and optoelectronic properties of janus -dendrimer-type multivalent donor-acceptor systems
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A convergent, multistep protocol was employed for the synthesis of a Janus-type multivalent donor-acceptor system. The synthetic approach is based on a Sonogashira cross-coupling of two differently ferrocene-(Fc) substituted dendrons and a final sixfold [
- Dengiz, Cagatay,Breiten, Benjamin,Gisselbrecht, Jean-Paul,Boudon, Corinne,Trapp, Nils,Schweizer, W. Bernd,Diederich, Fran?ois
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p. 882 - 896
(2015/01/30)
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- Optically active, amphiphilic poly(meta -phenylene ethynylene)s: Synthesis, hydrogen-bonding enforced helix stability, and direct AFM observation of their helical structures
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Optically active, amphiphilic poly(meta-phenylene ethynylene)s (PPEa) bearing l- or d-alanine-derived oligo(ethylene glycol) side chains connected to the backbone via amide linkages were prepared by microwave-assisted polycondensation. PPEa's exhibited an intense Cotton effect in the π-conjugated main-chain chromophore regions in various polar and nonpolar organic solvents due to a predominantly one-handed helical conformation stabilized by an intramolecular hydrogen-bonding network between the amide groups of the pendants. The stable helical structure was retained in the bulk and led to supramolecular column formation from stacked helices in oriented polymer films as evidenced by X-ray diffraction. Atomic force microscopy was used to directly visualize the helical structures of the polymers in two-dimensional crystalline layers with molecular resolution, and, for the first time, their absolute helical senses could unambiguously be determined.
- Banno, Motonori,Yamaguchi, Tomoko,Nagai, Kanji,Kaiser, Christian,Hecht, Stefan,Yashima, Eiji
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supporting information; experimental part
p. 8718 - 8728
(2012/06/30)
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- Conjugated oligoyne-bridged [60]fullerene molecular dumbbells: Syntheses and thermal and morphological properties
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Chemical Equation Presented A series of linear and star-shaped π-conjugated oligomer hybrids (2-5) composed of an oligoyne core, ranging from 1,3-butadiyne to 1,3,5,7,9,11-dodecahexayne, and fullerenyl end-capping groups has been synthesized and studied.
- Zhou, Ningzhang,Zhao, Yuming
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experimental part
p. 1498 - 1516
(2010/05/02)
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- Mixed-transition-metal acetylides: Synthesis and characterization of complexes with up to six different transition metals connected by carbon-rich bridging units
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The synthesis and reaction chemistry of heteromultimetallic transition-metal complexes by linking diverse metal-complex building blocks with multifunctional carbon-rich alkynyl-, benzene-, and bipyridyl-based bridging units is discussed. In context with this background, the preparation of [1-{(η2-dppf)(η5-C5H 5)RuC=C)-3-{(tBu2bpy)(CO)3ReC≡C}-5- (PPh2)-C6H3] (10) (dppf=1,1′- bis(diphenyl-phosphino)ferrocene; tBu2bpy = 4,4′-diferi-butyl- 2,2′-bipyridyl; Ph = phenyl) is described; this complex can react further, leading to the successful synthesis of heterometallic complexes of higher nuclearity. Heterotetrametallic transition-metal compounds were formed when 10 was reacted with [((η5-C5Me5)-RhCl 2}2] (18), [(Et2S)2PtCl2] (20) or -(tht)AuC≡C-bpy] (24) (Me = methyl; Et = ethyl ; tht = tetrahydrothiophene ; bpy = 2,2′-bipyridyl-5-yl). Complexes [1-((η2-dppf)(η5-C5H 5)RuC=C}-3-{(tBu2bpy)(CO)3ReC≡C)-5- (PPh2RhCl2(η5-C5Me 5)C6H3] (19), [{1-[(η2-dppf) (η5-C5H5)RuC=C]-3-[(tBu2-bpy) (CO).,ReC=-C]-5-(PPh2)C6H3}2- PtCl2] (21), and [1-((η2-dppf)(η5- C5H5)-RuC≡C}-3-((tBu2bpy)(CO) 3ReC≡C)-5-(PPh2AuC≡C-bpy)C6H 3] (25) were thereby obtained in good yield. After a prolonged time in solution, complex 25 undergoes a transmetallation reaction to produce [(tBu2bpy)(CO)3ReC≡C-bpy] (26). Moreover, the bipyridyl building block in 25 allowed the synthesis of Fe-Ru-Re-Au-Mo- (28) and Fe-Ru-Re-Au-Cu-Ti-based (30) assemblies on addition of [(nbd)Mo(CO) 4] (27), (nbd = 1,5-norbornadiene), or [{[Ti](μ-σ,π- C≡CSiMe3)2)Cu(N=CMe)]-[PF6] (29) ([Ti] = (η5-C5H4SiMe3)2Ti) to 25. The identities of 5, 6, 8, 10-12, 14-16, 19, 21, 25, 26, 28, and 30 have been confirmed by elemental analysis and IR, 1H, 13C{ 1H}, and 31P{1H} NMR spectroscopy. From selected samples ESI-TOF mass spectra were measured. The solid-state structures of 8, 12, 19 and 26 were additionally solved by single-crystal X-ray structure analysis, confirming the structural assignment made from spectroscopy.
- Packheiser, Rico,Ecorchard, Petra,Rueffer, Tobias,Lang, Heinrich
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scheme or table
p. 4948 - 4960
(2009/04/16)
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- Modular Synthesis of Benzene-Centered Porphyrin Trimers and a Dendritic Porphyrin Hexamer
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Rigid, star-shaped D3-symmetric arrays have been synthesized in which three porphyrin macrocyeles are attached to the 1,3, and 5 positions each of a benzene core through linkers consisting of collinear repetitive phenylethynyl units. Using the
- Mongin, Olivier,Papamicael, Cyril,Hoyler, Nicolas,Gossauer, Albert
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p. 5568 - 5580
(2007/10/03)
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