Through Structural Isomerism: Positional Effect of Alkyne Functionality on Molecular Optical Properties

2021 ◽  
Author(s):  
Nagaraju Nakka ◽  
Dushyant Kushavah ◽  
Sunil Kumar ◽  
Rajeev Ray ◽  
Diksha Gambhir ◽  
...  
Keyword(s):  
Optical Properties ◽  
Functional Group ◽  
Molecular Scaffolds ◽  
Structural Isomerism ◽  
Positional Effect

The study on the effect of alkyne functionality in manipulating the optical properties of donor-π-acceptor-type molecular scaffolds has been scarce in literature compared to alkene functional group. Here, two structurally...

PM2.5 Humic-like substances over Xi'an, China: Optical properties, chemical functional group, and source identification

2020 ◽  
Vol 234 ◽  
pp. 104784 ◽  
Author(s):  
Tian Zhang ◽  
Zhenxing Shen ◽  
Leiming Zhang ◽  
Zhuoyue Tang ◽  
Qian Zhang ◽  
...  
Keyword(s):  
Optical Properties ◽  
Source Identification ◽  
Functional Group ◽  
Chemical Functional Group

scholarly journals Selectively fluorinated cyclohexane building blocks: Derivatives of carbonylated all-cis-3-phenyl-1,2,4,5-tetrafluorocyclohexane

2015 ◽  
Vol 11 ◽  
pp. 2671-2676 ◽  
Author(s):  
Mohammed Salah Ayoup ◽  
David B Cordes ◽  
Alexandra M Z Slawin ◽  
David O'Hagan
Keyword(s):  
Functional Group ◽  
Building Blocks ◽  
Benzoic Acids ◽  
Molecular Scaffolds ◽  
Derivatives Of

Palladium catalysed carbonylation reactions using the meta- and para-iodo derivatives of all-cis-3-phenyl-1,2,4,5-tetrafluorocyclohexane (4) are illustrated as the start point for a variety of functional group interconversions. The resultant benzaldehyde and benzoic acids offer novel building blocks for further derivatisation and facilitate the incorporation of the facially polarised all-cis-1,2,4,5-tetrafluorocyclohexane motif into more advanced molecular scaffolds.

scholarly journals Positional Effect of π-extension in Triple Helicenes

2021 ◽  
Author(s):  
Alex van der Ham ◽  
Thomas Hansen ◽  
Hermen S. Overkleeft ◽  
Trevor A. Hamlin ◽  
Dmitri V. Filippov ◽  
...  
Keyword(s):  
Optical Properties ◽  
Rational Design ◽  
Marked Effect ◽  
Chemical Properties ◽  
Spectroscopic Properties ◽  
Positional Effect ◽  
Physico Chemical ◽  
Optical Applications ◽  
High Level ◽  
Vt Nmr

The targeted application of multiple helicenes in photo-optical applications requires their rational design. Toward this goal, we report on the synthesis of pyrene-based triple helicene 1 and investigate the positional effect of extension of the π-conjugated system on the photo-chemical and chiro-optical properties of triple helicenes. The conformational and aggregatory behavior of 1 were studied both experimentally using VT NMR spectroscopy and computationally using high-level DFT computations. Although π-extension was observed to have a marked effect on the spectroscopic properties of triple helicenes, comparison with other known π-extended helicenes reveals that the position at which π-extension is introduced is only of nominal importance. Our results thus suggest that the presence of a particular helicene motif is dominant in dictating the physico-chemical properties of triple helicenes.

How size, edge shape, functional groups and embeddedness influence the electronic structure and partial optical properties of graphene nanoribbons

2021 ◽  
Vol 23 (36) ◽  
pp. 20695-20701
Author(s):  
Jin Feng ◽  
Xinlong Mao ◽  
Hongxia Zhu ◽  
Zhe yang ◽  
Mengdi Cui ◽  
...  
Keyword(s):  
Optical Properties ◽  
Electronic Structure ◽  
Excited State ◽  
Band Structure ◽  
Functional Groups ◽  
Electron Distribution ◽  
State Energy ◽  
Functional Group ◽  
Graphene Nanoribbons ◽  
Excited State Energy

The size, edge shape, functional group and embeddedness affect the properties, including the band structure, excited state energy and electron distribution, of GNRs.

Assembly, growth and nonlinear thermo-optical properties of nitropeptides

2015 ◽  
Vol 17 (26) ◽  
pp. 16983-16990 ◽  
Author(s):  
Santu Bera ◽  
Deepak K. S. Ambast ◽  
Bipul Pal ◽  
Debasish Haldar
Keyword(s):  
Hydrogen Bond ◽  
Optical Properties ◽  
Phase Modulation ◽  
Functional Group ◽  
Self Phase Modulation ◽  
Π Stacking ◽  
Backbone Conformation

Irrespective of having the same functional group, π-conjugated system, chirality and backbone conformation as nitropeptides 1 and 3, nitropeptide 2 that forms a hydrogen bond and π–π stacking assisted dimer exhibits self-phase modulation.

scholarly journals Passerini-type reaction of boronic acids enables α-hydroxyketones synthesis

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Kai Yang ◽  
Feng Zhang ◽  
Tongchang Fang ◽  
Chaokun Li ◽  
Wangyang Li ◽  
...  
Keyword(s):  
Work Engagement ◽  
Multicomponent Reactions ◽  
Functional Group ◽  
Coupling Reaction ◽  
Boronic Acids ◽  
Molecular Scaffolds ◽  
Type Reaction ◽  
Carbon Nucleophiles ◽  
Mild Conditions ◽  
Operational Simplicity

AbstractMulticomponent reactions (MCRs) facilitate the rapid and diverse construction of molecular scaffolds with modularity and step economy. In this work, engagement of boronic acids as carbon nucleophiles culminates in a Passerini-type three-component coupling reaction towards the synthesis of an expanded inventory of α-hydroxyketones with skeletal diversity. In addition to the appealing features of MCRs, this protocol portrays good functional group tolerance, broad substrate scope under mild conditions and operational simplicity. The utility of this chemistry is further demonstrated by amenable modifications of bioactive products and pharmaceuticals as well as in the functionalization of products to useful compounds.

Preparation of phthalocyanines fused with four tetrathiafulvalene units via the functional group transformation of tetrakis(o-xylylenedithio)phthalocyanines with toluene/aluminum chloride

2014 ◽  
Vol 18 (10n11) ◽  
pp. 884-890 ◽  
Author(s):  
Takeshi Kimura ◽  
Tadafumi Chiba ◽  
Shiduko Nakajo
Keyword(s):  
Cyclic Voltammetry ◽  
Optical Properties ◽  
Aluminum Chloride ◽  
Nickel Complex ◽  
Functional Group ◽  
H Nmr ◽  
Vis Spectroscopy ◽  
Thiolate Anions ◽  
Functional Group Transformation ◽  
Tof Ms

Tetrakis(o-xylylenedithio)phthalocyanine 5 and its nickel complex 5-Ni were treated with aluminum chloride in toluene to eliminate the peripheral o-xylylene groups. The thiolate anions generated from 5 and 5-Ni were reacted with carbonyldiimidazole to produce phthalocyanines 6 and 6-Ni with four 1,3-dithiole-2-one rings, respectively. Phthalocyanine 7a having four ethylenedithiotetrathiafulvalene units was prepared via the condensation of 6-Ni with ethylenedithio-1,3-dithiole-2-thiones. The reaction of 6-Ni with bis(methylthio)-1,3-dithiole-2-thiones gave phthalocyanine 7b with the corresponding TTF units. The structures of the products were determined by 1 H NMR and MALDI-TOF-MS. Their electrochemical and optical properties were examined by cyclic voltammetry and UV-vis spectroscopy.

scholarly journals Positional Effect of π-extension in Triple Helicenes

2021 ◽  
Author(s):  
Alex van der Ham ◽  
Hermen S. Overkleeft ◽  
Dmitri V. Filippov ◽  
Grégory F. Schneider
Keyword(s):  
Optical Properties ◽  
Nmr Spectroscopy ◽  
Rational Design ◽  
Marked Effect ◽  
Chemical Properties ◽  
Positional Effect ◽  
Physico Chemical ◽  
Optical Applications ◽  
High Level ◽  
Vt Nmr

Application of multiple helicenes in photo‐optical applications requires their rational design. We therefore here report on the synthesis of pyrene‐based triple helicene 1, to study the positional effect of extension of the π‐conjugated system on the photo‐chemical and chiro‐optical properties of triple helicenes. The conformational and aggregatory behavior of 1 were studied both experimentally using VT NMR spectroscopy and computationally using high‐level DFT computations. Although π‐extension was observed to have a marked effect on the spectroscopy properties of triple helicenes, comparison with other known π‐extended helicenes reveals that the position at which π‐extension is introduced is only of nominal importance. Our results thus suggest that the presence of a particular helicene motive is dominant in dictating the physico‐chemical properties of triple helicenes.

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