271242-20-7

Basic information

• Product Name: Silane, [(4-bromophenyl)ethynyl]tris(1-methylethyl)-
• CAS NO: 271242-20-7
• Molecular Formula: C17H25BrSi
• Molecular Weight: 337.375
• Mol File: 271242-20-7.mol

Chemical Properties

• CAS DataBase Reference: Silane, [(4-bromophenyl)ethynyl]tris(1-methylethyl)-(CAS DataBase Reference)
• NIST Chemistry Reference: Silane, [(4-bromophenyl)ethynyl]tris(1-methylethyl)-(271242-20-7)
• EPA Substance Registry System: Silane, [(4-bromophenyl)ethynyl]tris(1-methylethyl)-(271242-20-7)

Safety Data

• Hazardous Substances Data: 271242-20-7(Hazardous Substances Data)

Upstream product

• 106-37-6 1.4-dibromobenzene 
• 89343-06-6 tris-iso-propylsilyl acetylene 
• 108-86-1 bromobenzene 
• 111409-79-1 1-bromo-2-(triisopropylsilyl)acetylene 
• 2297-64-5 p-bromophenylsulfonyl hydrazide 
• 98-58-8 4-bromobenzenesulfonyl chloride 
• 589-87-7 1,4-bromoiodobenzene 

Downstream Products

• 864070-21-3 (5-bromo-2-fluoro-phenyl)-{4-[(triisopropylsilyl)-ethynyl]-phenyl}-methanol 
• 307930-50-3 4-[(triisopropylsilanyl)-ethynyl]-benzoic acid 
• 1616766-87-0 methyl 4-((triisopropylsilyl)ethynyl)benzoate 

Relevant articles and documents

Preparation of a cyclic polyphenylene array for a chiral-type carbon nanotube segment

DielsAlder reaction of cyclic biphenylyleneacetylene compound 3 with tetraphenylcyclopentadienone (5) realized the preparation of large-sized cyclic polyphenylene array 4. This is the first example of a cyclic polyphenylene array with a complete ring arrangement of a chiral-type CNT segment with (12,3)-structure. Transformation of 4 to the chiral-type CNT segment was attempted, but resulted in the formation of a complicated mixture probably due to the partial dehydrogenation and/or the partial elimination about the long alkyl chains. Rather efficient blue emission of the cyclic compounds 3 and 4 was discussed utilizing fluorescence quantum efficiencies and lifetimes both in their solid state and in their solution. By thermal analyses triple-melting behavior of 3 was clarified.

Synthesis and Photophysical Properties of 1,1,4,4-Tetracyanobutadienes Derived from Ynamides Bearing Fluorophores**

1,1,4,4-Tetracyanobutadienes (TCBDs) bearing a large diversity of fluorophores were prepared following a multi-step synthesis. In a crucial last step, all compounds were obtained from the corresponding ynamides, which were particularly suitable for the formation of the TCBDs in the presence of tetracyanoethylene via a [2+2] cycloaddition/retroelectrocyclization step (CA-RE). Several fluorenyl derivatives in addition to phenanthrenyl and terphenyl ones provided ynamide-based TCBDs affording remarkable emission properties covering a large range of wavelengths. Those compounds emit both in solid state and in solution from the visible region to the NIR range, depending on the molecular structures. Quantum yields in cyclohexane reached unforeseen values for such derivatives, up to 7.8 %. A huge sensitivity to the environment of the TCBDs has also been unraveled for most of the compounds since we observed a dramatic fall of the quantum yields when changing the solvent from cyclohexane to toluene, while they are almost non-emissive in dichloromethane.

Copolymers based on trialkylsilylethynyl-phenyl substituted benzodithiophene building blocks for efficient organic solar cells

Non-fullerene acceptors have received a great deal of attention over the past several years, and numerous modifications on the molecular structures significantly boosted the power conversion efficiencies (PCEs) of organic solar cells (OSCs). To be a match, a promising polymer donor is urgently needed. Herein, we report a wide bandgap donor with alternating fluorinated benzotriazole (FTAZ) and triisopropylsilylethynyl-phenyl substituted benzodithiophene. Strategically, the lateral benzene and acetylene motifs induce a down-shift of the HOMO energy level, and the alkylsilyl facilitates inter-chain interactions and modulates the solubility. The new polymer exhibits a strong solution pre-aggregation ability that influences the intermixed morphology and optimizing methods of OSCs. When blended with the easily accessible acceptor IDIC, a respective PCE of 7.81% with aVocof 0.928 V has been demonstrated. We investigated the impact of molecular weights on the optical and electrochemical properties, charge transport, blend morphology, and photovoltaic parameters, and the result indicates that a highMnis desired for improving the quality of the solution-processed films. The acquired results reveal that trialkylsilylethynyl-phenyl is a promising multi-functional side chain scaffold for developing promising conjugated molecules.

Development of helical aromatic amide foldamers with a diphenylacetylene backbone

We designed and synthesized aromatic polyamides with a diphenylacetylene backbone, α-DPA and β-DPA, bearing (S)-α-and (S)-β-methyl-substituted triethyleneglycol (TEG) side chains, respectively, and examined their conformations in solution. Both polymers exhibit strong, solvent polarity-dependent circular dichroism spectra, which indicated that they take helical conformations in low-polarity solvents. The spectra were mirror images, depending on the chiral position of the side chains. Thus, the polyamide α-DPA bearing (S)-α-methyl-substituted TEG groups takes a left-handed helical conformation, while the polyamide β-DPA with (S)-β-methyl-substituted TEG groups takes a right-handed helical conformation. The difference in the screw sense of α-DPA and β-DPA would be caused by the steric interaction between the main chain and the side chain, as observed in poly(p-benzamide) possessing (S)-β-methyl-substituted TEG side chains (β-PA) because the large cavity of the helical structure of DPA would disturb the solvophobically induced helical folding. Detailed conformational analyses of the oligoamides 6-12 with β-methyl-substituted TEG groups were conducted. Theoretical calculations indicated that the oligoamides with β-methyl-substituted TEG groups exist in a helical conformation with a cavity of 7 ? in diameter. The 1H NMR spectra of the oligomers revealed interactions with small anions such as chloride and acetate anions and with pyridinium cations.

Resistance to unwanted photo-oxidation of multi-acene molecules

Although long acenes remain a key class of π- conjugated molecules for numerous applications, photoinduced oxidation upon exposure of the acene to light, often through sensitization of 1O2, is an important reaction requiring mitigation for most applications. In response to this ongoing challenge, this paper presents a series of four new diarylethynyl-substituted long acenes-three tetracenes and one anthradithiophene-in which the arylene pendants are either benzene, naphthalene, or anthracene. UV/vis and fluorescence spectroscopy reveals that the anthracene-substituted derivatives fluoresce poorly (φ 0.01). Although all four long acenes react with 1O2 at expected rates when an external photosensitizer is included and show the expected changes in fluorescence to accompany these reactions, the anthracene-substituted derivatives resist direct photoinduced oxidation. Through a combination of mechanistic experiments, we conclude that rapid nonradiative decay of the anthracene-substituted derivatives, perhaps because of inter-arene torsions that emerge in theoretical geometry optimizations, makes these compounds poor photosensitizers for 1O2 or other reactive oxygen species. This discovery opens new design possibilities for extended acene structures with improved photochemical stability.

Chiral hydrogen-bonded supramolecular capsules: Synthesis, characterization and complexation of C70

Two supramolecular nanocapsules were generated by multi-component self-assembly of the novel bisphosphoric acid (R,R)-6 with suitable bis- and trisamidines. The resulting chiral, hydrogen-bonded capsules are stable even in polar media and at low concentrations and can be employed for the binding of C70-fullerene in solution.

Sterically Controlled Late-Stage C-H Alkynylation of Arenes

Phenylacetylenes are key structural motifs in organic chemistry, which find widespread applications in bioactive molecules, synthetic intermediates, functional materials, and reagents. These molecules are typically prepared from prefunctionalized starting materials, e.g. using the Sonogashira coupling, or using directing group-based C-H activation strategies. While highly efficient, these approaches remain limited by their inherent selectivities for specific regioisomers. Herein we present a complementary approach based on an arene-limited nondirected C-H activation. The reaction is predominantly controlled by steric rather than electronic factors and thereby gives access to a complementary product spectrum with respect to traditional methods. A broad scope as well as the suitability of this protocol for late-stage functionalization are demonstrated.

Borazino-Doped Polyphenylenes

The divergent synthesis of two series of borazino-doped polyphenylenes, in which one or more aryl units are replaced by borazine rings, is reported for the first time, taking advantage of the decarbonylative [4 + 2] Diels-Alder cycloaddition reaction between ethynyl and tetraphenylcyclopentadienone derivatives. Because of the possibility of functionalizing the borazine core with different groups on the aryl substituents at the N and B atoms of the borazino core, we have prepared borazino-doped polyphenylenes featuring different doping dosages and orientations. To achieve this, two molecular modules were prepared: a core and a branching unit. Depending on the chemical natures of the central aromatic module and the reactive group, each covalent combination of the modules yields one exclusive doping pattern. By means of this approach, three- and hexa-branched hybrid polyphenylenes featuring controlled orientations and dosages of the doping B3N3 rings have been prepared. Detailed photophysical investigations showed that as the doping dosage is increased, the strong luminescent signal is progressively reduced. This suggests that the presence of the B3N3 rings engages additional deactivation pathways, possibly involving excited states with an increasing charge-separated character that are restricted in the full-carbon analogues. Notably, a strong effect of the orientational doping on the fluorescence quantum yield was observed for those hybrid polyphenylene structures featuring low doping dosages. Finally, we showed that Cu-catalyzed 1,3-dipolar cycloaddition is also chemically compatible with the BN core, further endorsing the inorganic benzene as a versatile aromatic scaffold for engineering of molecular materials with tailored and exploitable optoelectronic properties.

Palladium-Catalyzed Desulfitative Cross-Coupling of Arylsulfonyl Hydrazides with Terminal Alkynes: A General Approach toward Functionalized Internal Alkynes

A palladium-catalyzed Sonogashira-type coupling between arylsulfonyl hydrazides and terminal alkynes via Ar(C)-S bond cleavage is disclosed, which enables the general synthesis of functionalized internal alkynes, especially the Br-substituted ones, in good to excellent yields under acid- and base-free conditions.

Reversible Photomodulation of Electronic Communication in a π-Conjugated Photoswitch-Fluorophore Molecular Dyad

The extent of electronic coupling between a boron dipyrromethene (BODIPY) fluorophore and a diarylethene (DAE) photoswitch has been modulated in a covalently linked molecular dyad by irradiation with either UV or visible light. In the open isomer, both moieties can be regarded as individual chromophores, while in the closed form the lowest electronic (S0→S1) transition of the dyad is slightly shifted, enabling photomodulation of its fluorescence. Transient spectroscopy confirms that the dyad behaves dramatically different in the two switching states: while in the open isomer it resembles an undisturbed BODIPY fluorophore, in the closed isomer no fluorescence occurs and instead a red-shifted DAE behavior prevails.