19752-57-9Relevant articles and documents
FHBC, a Hexa-peri-hexabenzocoronene–Fluorene Hybrid: A Platform for Highly Soluble, Easily Functionalizable HBCs with an Expanded Graphitic Core
Navale, Tushar S.,Ivanov, Maxim V.,Hossain, Mohammad M.,Rathore, Rajendra
, p. 790 - 794 (2018)
Materials based upon hexa-peri-hexabenzocoronenes (HBCs) show significant promise in a variety of photovoltaic applications. There remains the need, however, for a soluble, versatile, HBC-based platform, which can be tailored by incorporation of electroactive groups or groups that can prompt self-assembly. The synthesis of a HBC–fluorene hybrid is presented that contains an expanded graphitic core that is highly soluble, resists aggregation, and can be readily functionalized at its vertices. This new HBC platform can be tailored to incorporate six electroactive groups at its vertices, as exemplified by a facile synthesis of a representative hexaaryl derivative of FHBC. Synthesis of new FHBC derivatives, containing electroactive functional groups that can allow controlled self-assembly, may serve as potential long-range charge-transfer materials for photovoltaic applications.
Size Matters: Influence of Gold-to-Ligand Ratio and Sulfur-Sulfur Distance of Linear Thioether Heptamers on the Size of Gold Nanoparticles
Lehmann, Mario,Peters, Erich Henrik,Mayor, Marcel
, (2017)
A systematic investigation of two parameters steering the size of linear octadentate heptamer-coated gold nanoparticles (AuNPs) is presented, being i) the chemical structure (sulfur-sulfur distance) of the coating thioether heptamer ligand and ii) the ratio of ligand to tetrachloroauric acid (HAuCl4) reduced during the formation of the AuNPs. For this purpose, a novel terphenyl-based thioether heptamer (Ter) is synthesized via an end-capping oligomerization strategy, comprising an increased distance between neighboring sulfur atoms in the ligand backbone compared to the meta-xylene- (Xyl) and tetraphenylmethane- (TPM) based heptamers. While for both investigated parameters a clear trend to various-sized NPs is shown, a stronger influence in the resulting sizes is observed by alteration of ligand to gold-ratio. Remarkable processability- and long-term stability-features were observed for AuNPs stabilized by the bulky tetraphenylmethane-based heptamer (TPM).
Visible-Light-Photosensitized Aryl and Alkyl Decarboxylative Functionalization Reactions
Patra, Tuhin,Mukherjee, Satobhisha,Ma, Jiajia,Strieth-Kalthoff, Felix,Glorius, Frank
supporting information, p. 10514 - 10520 (2019/07/12)
Despite significant progress in aliphatic decarboxylation, an efficient and general protocol for radical aromatic decarboxylation has lagged far behind. Herein, we describe a general strategy for rapid access to both aryl and alkyl radicals by photosensitized decarboxylation of the corresponding carboxylic acids esters followed by their successive use in divergent carbon–heteroatom and carbon–carbon bond-forming reactions. Identification of a suitable activator for carboxylic acids is the key to bypass a competing single-electron-transfer mechanism and “switch on” an energy-transfer-mediated homolysis of unsymmetrical σ-bonds for a concerted fragmentation/decarboxylation process.
H-Bonded Duplexes based on a Phenylacetylene Backbone
Swain, Jonathan A.,Iadevaia, Giulia,Hunter, Christopher A.
supporting information, p. 11526 - 11536 (2018/09/18)
Complementary phenylacetylene oligomers equipped with phenol and phosphine oxide recognition sites form stable multiply H-bonded duplexes in toluene solution. Oligomers were prepared by Sonogashira coupling of diiodobenzene and bis-acetylene building blocks in the presence of monoacetylene chain terminators. The product mixtures were separated by reverse phase preparative high-pressure liquid chromatography to give a series of pure oligomers up to seven recognition units in length. Duplex formation between length complementary homo-oligomers was demonstrated by 31P NMR denaturation experiments using dimethyl sulfoxide as a competing H-bond acceptor. The denaturation experiments were used to determine the association constants for duplex formation, which increase by nearly 2 orders of magnitude for every phenol-phosphine oxide base-pair added. These experiments show that the phenylacetylene backbone supports formation of extended duplexes with multiple cooperative intermolecular H-bonding interactions, and together with previous studies on the mixed sequence phenylacetylene 2-mer, suggest that this supramolecular architecture is a promising candidate for the development of synthetic information molecules that parallel the properties of nucleic acids.
Preparation method of 3, 5-dibromo iodobenzene
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Paragraph 0014; 0016; 0017, (2016/11/24)
The present invention discloses a preparation method of 3, 5-dibromo iodobenzene. The preparation method comprises the following steps: Step 1, p-Iodoaniline and absolute ethyl alcohol are added into a container, and dibromodimethyl hydantoin is added int
Synthesis and optoelectronic properties of janus -dendrimer-type multivalent donor-acceptor systems
Dengiz, Cagatay,Breiten, Benjamin,Gisselbrecht, Jean-Paul,Boudon, Corinne,Trapp, Nils,Schweizer, W. Bernd,Diederich, Fran?ois
, p. 882 - 896 (2015/01/30)
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 [
Synthesis of branched tetranuclear alkynylplatinum(II) terpyridine complexes and their photophysical properties
Xu, Peng,Ye, Shifan,Wu, Haotian,Yan, Zhiping,Jia, Hongxing,Du, Pingwu
, p. 3486 - 3490 (2014/06/10)
Herein we report the synthesis of two luminescent branched tetranuclear alkynylplatinum(II) complexes {[Pt(tBu3-tpy)]2[Ar(CC) 4][Pt(tBu3-tpy)]}2(PF6)4 (I and II; tBu3-
Three-component asymmetric catalytic ugi reaction - Concinnity from diversity by substrate-mediated catalyst assembly
Zhao, Wenjun,Huang, Li,Guan, Yong,Wulff, William D.
supporting information, p. 3436 - 3441 (2014/04/03)
The first chiral catalyst for the three-component Ugi reaction was identified as a result of a screen of a large set of different BOROX catalysts. The BOROX catalysts were assembled in situ from a chiral biaryl ligand, an amine, water, BH3×SMe2, and an alcohol or phenol. The catalyst screen included 13 different ligands, 12 amines, and 47 alcohols or phenols. The optimal catalyst system (LAP 8-5-47) provided α-amino amides from an aldehyde, a secondary amine, and an isonitrile with excellent asymmetric induction. The catalytically active species is proposed to be an ion pair that consists of the chiral boroxinate anion and an iminium cation. Harmonious arrangement of parts: A screen of BOROX catalysts that were generated in situ from 13 different ligands and 47 alcohols led to the identification of an effective combination for the catalytic asymmetric three-component Ugi reaction. Experimental results suggest that the catalyst is a chiral polyborate anion, which then forms an ion pair with the iminium cation that is generated from aldehyde and secondary amine.
Mixed-transition-metal acetylides: Synthesis and characterization of complexes with up to six different transition metals connected by carbon-rich bridging units
Packheiser, Rico,Ecorchard, Petra,Rueffer, Tobias,Lang, Heinrich
scheme or table, p. 4948 - 4960 (2009/04/16)
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.
Convergent synthesis of platinum-acetylide dendrimers
Onitsuka, Kiyotaka,Fujimoto, Masanori,Kitajima, Hotaka,Ohshiro, Nobuaki,Takei, Fumie,Takahashi, Shigetoshi
, p. 6433 - 6446 (2007/10/03)
An efficient convergent route to the main chain type of organometallic dendrimers, in which platinum moieties are linked by 1,3,5-triethynylbenzene, has been developed. The synthesis of platinum-acetylide dendrons involved the use of two types of trialkylsilyl groups for protection of the terminal acetylene. The platinum-acetylide dendrimers were prepared up to the third generation by reacting dendrons with a triplatinum core and a tetraplatinum core. Spectroscopic characterization and trace experiments by gel permeation chromatography indicated that the dendrimer molecules have no structural defects. Although a π-conjugated system was used as the bridging ligand, electronic and fluorescence spectra suggested that the interaction among the platinum-acetylide moieties in the dendrimers was small.
