Synthesis of a Blue‐Emissive Azaborathia[9]helicene by Silicon‐Boron Exchange from Unusual Atropisomeric Teraryls

Angewandte Chemie International Edition, Год журнала: 2023, Номер 62(30)

Опубликована: Май 13, 2023

We report the concise synthesis and chir(optical) properties of an azaborathia[9]helicene consisting two thienoazaborole motifs. The key intermediate, a highly congested teraryl with nearly parallel isoquinoline moieties, was generated as mixture atropisomers upon fusion central thiophene ring dithienothiophene moiety. These diastereomers were characterized by single crystal X-ray analysis revealing intriguing interactions in solid state. Subsequent insertion boron into aromatic scaffold via silicon-boron exchange involving triisopropylsilyl groups fixed helical geometry, thereby establishing novel method for preparation azaboroles. ligand at final step afforded blue emitter displaying fluorescence quantum yield 0.17 CH2 Cl2 excellent configurational stability. Detailed structural theoretical investigation unusual helicene provide insights their isomerization processes.

Язык: Английский

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Dibenzyl Isophthalates as Versatile Hosts in Room Temperature Phosphorescence Host-Guest Systems

Chemical Science, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

Simple yet powerful: dibenzyl isophthalates are easy to modify hosts for room-temperature phosphorescence. These systems achieve record-setting quantum yields and lifetimes while offering unprecedented color tunability across the visible spectrum.

Язык: Английский

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Structure and photophysical properties of furoquinoline aza-helicenes: Fluorescence enhancement by protonation

Dyes and Pigments, Год журнала: 2024, Номер 225, С. 112032 - 112032

Опубликована: Март 2, 2024

Язык: Английский

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Ambient Temperature Dehydrogenative C(Ar)–H Carbonylative Lactamization of 2-Arylanilines Using DMF as C1-Source

Organic Letters, Год журнала: 2023, Номер 25(15), С. 2611 - 2615

Опубликована: Апрель 7, 2023

The direct dehydrogenative C-H cleaving carbonylative lactamization of 2-arylanilines promoted by visible light and potassium bases is reported. Solvent DMF acts as the sole carbonyl source in absence an oxidant. irreversible release hydrogen gas drags this reaction to stable phenanthridinone products. This work provides a conversion broad range various phenanthridinones. method could be applied synthesis bioactive molecules organic optoelectronic materials.

Язык: Английский

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Construction and Phosphorescence Behavior of S/Se-Heteroaromatics/Phenanthrene-Fused Hetero[9]helicenes

Organic Letters, Год журнала: 2023, Номер 25(36), С. 6715 - 6719

Опубликована: Сен. 1, 2023

Three S/Se-hetero[9]helicenes were synthesized by an assembly strategy of two building blocks, phenanthrene and ternary fused S/Se-heteroaromatic ring, characterized single-crystal X-ray diffraction analysis. Their phosphorescence emission gave a long-lived lifetime at the millisecond level. In addition, high configurational stability enantiomer (+)-[9]BH-1a was observed without change under both conditions 300 °C in solid state for 18 h 200 solution 1,2-dichlorobenzene 10 h.

Язык: Английский

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Resolution of 9,10-Diketo[7]helicene and Its Use in One-Step Preparation of Helicene-Based D–A–D Push–Pull Systems

The Journal of Organic Chemistry, Год журнала: 2024, Номер 89(11), С. 7495 - 7502

Опубликована: Май 28, 2024

Racemic 9,10-diketo[7]helicene was successfully separated into enantiomers using a reversible and stereoselective reaction with 2,2'-diamino-1,1'-binaphthalene moderate yields but remarkable purity (>99% de). The enantiomerically pure diketone used as convenient starting material for the preparation of helicene-based push-pull molecules, which incorporated aza-aryl acceptors diarylaminophenylene donor groups in single step. A series six systems, along three reference molecules without donors, were prepared studied UV/vis fluorescence measurements, circular dichroism, DFT calculations.

Язык: Английский

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HFIP-promoted halo-carbocyclizations of N- and O-tethered arene–alkene substrates to access all halo (X = Br, I, Cl)-functionalized tetrahydroquinoline and chroman cores

Organic & Biomolecular Chemistry, Год журнала: 2022, Номер 20(41), С. 8136 - 8144

Опубликована: Янв. 1, 2022

A new method for the stereoselective metal-, additive- and oxidant-free Friedel-Crafts-type halo-carbocyclization of N- O-tethered arene-olefin substrates is reported, involving reaction with a suitable electrophilic halogenating reagent (NXS/DCDMH) in hexafluoroisopropanol. All halo (X = Br, I, Cl)-functionalized tetrahydroquinolines chromans were obtained excellent yields high levels diastereocontrol (dr >99 : 1), these products successfully transformed into synthetically useful compounds such as dihydroquinolines partial or full azahelicene compounds.

Язык: Английский

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Adsorption and Self-Aggregation of Chiral [5]-Aza[6]helicenes on DNA Architecture: A Molecular Dynamics Study

The Journal of Physical Chemistry B, Год журнала: 2023, Номер 127(39), С. 8285 - 8295

Опубликована: Сен. 26, 2023

Helicenes are an extremely interesting class of conjugated molecules without asymmetric carbon atoms but with intrinsic chirality. These can interact double-stranded chiral B-DNA architecture, modifying after their adsorption the hydrophilicity exposed by DNA to biological environment. They also form ordered structures due self-aggregation processes possible different light emissions. Following initial studies based on molecular mechanics (MM) and dynamics (MD) simulations regarding process 5-aza[5]helicenes B-DNA, this theoretical work investigates interaction between (M)- (P)-5-aza[6]helicenes double-helix DNA. Initially, pure single enantiomer is studied. Possible preferential absorption in minor or major grooves occur. Afterward, enantiopure compounds (P)-5-aza[6]helicenes, potentially occurring a racemic mixture at concentrations, was investigated, taking into consideration both competitive helicenes' process. The structural selectivity binding role helicene concentration interesting. In addition, ability that follow its thanks favorable van der Waals intermolecular interactions, curious.

Язык: Английский

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Synthesis of a Blue‐Emissive Azaborathia[9]helicene by Silicon‐Boron Exchange from Unusual Atropisomeric Teraryls

Angewandte Chemie, Год журнала: 2023, Номер 135(30)

Опубликована: Май 13, 2023

Abstract We report the concise synthesis and chir(optical) properties of an azaborathia[9]helicene consisting two thienoazaborole motifs. The key intermediate, a highly congested teraryl with nearly parallel isoquinoline moieties, was generated as mixture atropisomers upon fusion central thiophene ring dithienothiophene moiety. These diastereomers were characterized by single crystal X‐ray analysis revealing intriguing interactions in solid state. Subsequent insertion boron into aromatic scaffold via silicon‐boron exchange involving triisopropylsilyl groups fixed helical geometry, thereby establishing novel method for preparation azaboroles. ligand at final step afforded blue emitter displaying fluorescence quantum yield 0.17 CH 2 Cl excellent configurational stability. Detailed structural theoretical investigation unusual helicene provide insights their isomerization processes.

Язык: Английский

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Modification of optical properties in helicenes via construction of phosphine oxide-based push-pull systems

Dyes and Pigments, Год журнала: 2022, Номер 210, С. 111039 - 111039

Опубликована: Дек. 21, 2022

Язык: Английский

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