Effect of fluorination and symmetry on the properties of polymeric photovoltaic materials based on an asymmetric building block

The facile preparation of three regioisomeric thienopyrrolocarbazoles applying a convenient C-H activation approach is presented. Derived from indolo[3,2,1-<i>jk</i>]carbazole, the incorporation of thiophene into the triarylamine framework significantly impacted the molecular properties of the parent scaffold. The developed thienopyrrolocarbazoles enrich the family of triarylamine donors and constitute a novel building block for functional organic materials.

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Thienopyrrolocarbazoles: New Building Blocks for Functional Organic Materials

10.26434/chemrxiv.7777343 ◽

2019 ◽

Author(s):

Dorian Bader ◽

Johannes Fröhlich ◽

Paul Kautny

Keyword(s):

Building Block ◽

Organic Materials ◽

Building Blocks ◽

Molecular Properties ◽

The Family ◽

Facile Preparation

The facile preparation of three regioisomeric thienopyrrolocarbazoles applying a convenient C-H activation approach is presented. Derived from indolo[3,2,1-<i>jk</i>]carbazole, the incorporation of thiophene into the triarylamine framework significantly impacted the molecular properties of the parent scaffold. The developed thienopyrrolocarbazoles enrich the family of triarylamine donors and constitute a novel building block for functional organic materials.

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PyroMEMS as Future Technological Building Blocks for Advanced Microenergetic Systems

Micromachines ◽

10.3390/mi12020118 ◽

2021 ◽

Vol 12 (2) ◽

pp. 118

Author(s):

Jean-Laurent Pouchairet ◽

Carole Rossi

Keyword(s):

Building Block ◽

Building Blocks ◽

Small Scale ◽

Technological Evolution ◽

Research Groups ◽

Function Block ◽

The Past ◽

New Methods ◽

Safety And Reliability ◽

Electronically Controllable

For the past two decades, many research groups have investigated new methods for reducing the size and cost of safe and arm-fire systems, while also improving their safety and reliability, through batch processing. Simultaneously, micro- and nanotechnology advancements regarding nanothermite materials have enabled the production of a key technological building block: pyrotechnical microsystems (pyroMEMS). This building block simply consists of microscale electric initiators with a thin thermite layer as the ignition charge. This microscale to millimeter-scale addressable pyroMEMS enables the integration of intelligence into centimeter-scale pyrotechnical systems. To illustrate this technological evolution, we hereby present the development of a smart infrared (IR) electronically controllable flare consisting of three distinct components: (1) a controllable pyrotechnical ejection block comprising three independently addressable small-scale propellers, all integrated into a one-piece molded and interconnected device, (2) a terminal function block comprising a structured IR pyrotechnical loaf coupled with a microinitiation stage integrating low-energy addressable pyroMEMS, and (3) a connected, autonomous, STANAG 4187 compliant, electronic sensor arming and firing block.

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Quantitative Determination of the Effects of He-Ne Laser Irradiation on Seed Thermodynamics, Germination Attributes and Metabolites of Safflower (Carthamus tinctorius L.) in Relation with the Activities of Germination Enzymes

Agronomy ◽

10.3390/agronomy11071411 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1411

Author(s):

Rashida Perveen ◽

Xiukang Wang ◽

Yasir Jamil ◽

Qasim Ali ◽

Shafaqat Ali ◽

...

Keyword(s):

Seed Germination ◽

Energy Levels ◽

Soluble Sugars ◽

Building Blocks ◽

Carthamus Tinctorius ◽

Fast Decline ◽

Seed Irradiation ◽

Seed Reserves ◽

Positive Correlations

The present investigation was undertaken to assess the effects of different doses (100, 300, and 500 mJ) of low power He–Ne laser (632.8 nm) irradiation on seed germination and thermodynamics attributes and activities of potential germinating enzymes in relation with changes in seed metabolites. He–Ne laser seed irradiation increased the amylase (Amy), protease (Pro) and glucosidase (Gluco) activities, with a significant improvement in seed thermodynamics and seed germination attributes. A fast increase was found in free fatty acids (FFA), free amino acids (FAA), chlorophyll (Chl), carotenoids (Car), total soluble sugars (TSS) and reducing sugars (RS) in laser treated seeds in parallel with fast decline in seed oil contents and total soluble proteins (TSP). Significant positive correlations were recorded in laser-induced enhanced seed energy levels, germination, activities of germination enzymes with levels of FAA, FFA, Chl, TSS and RS, but a negative correlation with the levels of TSP and oil. In conclusion, the seed treatment with 100 and 300 mJ He–Ne laser was more effective to improve the seed germination potential associated with an improvement in seed energy levels due to increased activities of germination enzymes due to the speedy breakdown of seed reserves to simple metabolites as building blocks.

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Lipase Catalyzed Synthesis of Enantiopure Precursors and Derivatives for β-Blockers Practolol, Pindolol and Carteolol

Catalysts ◽

10.3390/catal11040503 ◽

2021 ◽

Vol 11 (4) ◽

pp. 503

Author(s):

Morten Gundersen ◽

Guro Austli ◽

Sigrid Løvland ◽

Mari Hansen ◽

Mari Rødseth ◽

...

Keyword(s):

Building Block ◽

Kinetic Resolution ◽

Enantiomeric Excess ◽

Catalytic Amount ◽

Building Blocks ◽

Β Blocker ◽

Β Blockers ◽

Optical Rotations ◽

Reported Data ◽

By Products

Sustainable methods for producing enantiopure drugs have been developed. Chlorohydrins as building blocks for several β-blockers have been synthesized in high enantiomeric purity by chemo-enzymatic methods. The yield of the chlorohydrins increased by the use of catalytic amount of base. The reason for this was found to be the reduced formation of the dimeric by-products compared to the use of higher concentration of the base. An overall reduction of reagents and reaction time was also obtained compared to our previously reported data of similar compounds. The enantiomers of the chlorohydrin building blocks were obtained by kinetic resolution of the racemate in transesterification reactions catalyzed by Candida antarctica Lipase B (CALB). Optical rotations confirmed the absolute configuration of the enantiopure drugs. The β-blocker (S)-practolol ((S)-N-(4-(2-hydroxy-3-(isopropylamino)propoxy)phenyl)acetamide) was synthesized with 96% enantiomeric excess (ee) from the chlorohydrin (R)-N-(4-(3-chloro-2 hydroxypropoxy)phenyl)acetamide, which was produced in 97% ee and with 27% yield. Racemic building block 1-((1H-indol-4-yl)oxy)-3-chloropropan-2-ol for the β-blocker pindolol was produced in 53% yield and (R)-1-((1H-indol-4-yl)oxy)-3-chloropropan-2-ol was produced in 92% ee. The chlorohydrin 7-(3-chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one, a building block for a derivative of carteolol was produced in 77% yield. (R)-7-(3-Chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one was obtained in 96% ee. The S-enantiomer of this carteolol derivative was produced in 97% ee in 87% yield. Racemic building block 5-(3-chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one, building block for the drug carteolol, was also produced in 53% yield, with 96% ee of the R-chlorohydrin (R)-5-(3-chloro-2-hydroxypropoxy)-3,4-dihydroquinolin-2(1H)-one. (S)-Carteolol was produced in 96% ee with low yield, which easily can be improved.

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Dimerization and oligomerization of DNA-assembled building blocks for controlled multi-motion in high-order architectures

Nature Communications ◽

10.1038/s41467-021-23532-y ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Ling Xin ◽

Xiaoyang Duan ◽

Na Liu

Keyword(s):

Building Block ◽

Degrees Of Freedom ◽

Building Blocks ◽

Single Type ◽

Hierarchical Assembly ◽

Optical Responses ◽

Self Association ◽

Living Organisms ◽

Order Structures ◽

Chiral System

AbstractIn living organisms, proteins are organized prevalently through a self-association mechanism to form dimers and oligomers, which often confer new functions at the intermolecular interfaces. Despite the progress on DNA-assembled artificial systems, endeavors have been largely paid to achieve monomeric nanostructures that mimic motor proteins for a single type of motion. Here, we demonstrate a DNA-assembled building block with rotary and walking modules, which can introduce new motion through dimerization and oligomerization. The building block is a chiral system, comprising two interacting gold nanorods to perform rotation and walking, respectively. Through dimerization, two building blocks can form a dimer to yield coordinated sliding. Further oligomerization leads to higher-order structures, containing alternating rotation and sliding dimer interfaces to impose structural twisting. Our hierarchical assembly scheme offers a design blueprint to construct DNA-assembled advanced architectures with high degrees of freedom to tailor the optical responses and regulate multi-motion on the nanoscale.

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Synthesis of π-Conjugated Polymers Containing Benzotriazole Units via Palladium-Catalyzed Direct C-H Cross-Coupling Polycondensation for OLEDs Applications

Polymers ◽

10.3390/polym13020254 ◽

2021 ◽

Vol 13 (2) ◽

pp. 254

Author(s):

Dong Han ◽

Jingwen Li ◽

Qiang Zhang ◽

Zewang He ◽

Zhiwei Wu ◽

...

Keyword(s):

Conjugated Polymers ◽

Quantum Efficiency ◽

Cross Coupling ◽

Building Blocks ◽

Gravimetric Analysis ◽

19F Nmr Spectra ◽

Light Emitting ◽

Molecular Weights ◽

Palladium Catalyzed ◽

Red Luminescence

Four D-π-A conjugated polymers, namely P1–P4, which contain benzotriazole building blocks in their backbone as acceptor, are synthesized via palladium-catalyzed direct C-H cross-coupling polycondensation of 5,6-difluorobenzotriazole with different thiophene derivatives, including 3-octylthiophene, 2,2’-bithiophene, thieno[3,4-b][1,4]dioxine, and 4,4-dioctyl-4H-silolo-[3,2-b:4,5-b’]dithiophene as donor units, respectively. Taking the polymer P1 as an example, the chemical structure of the polymer is demonstrated by 1H and 19F NMR spectra. The optical, electrochemical, and thermal properties of these polymers are assessed by UV–vis absorption and fluorescence spectroscopy, cyclic voltammetry (CV), and thermal gravimetric analysis (TGA), respectively. DFT simulations of all polymers are also performed to understand their physicochemical properties. Furthermore, P1 and P2, which have relatively higher molecular weights and better fluorescent quantum efficiency than those of P3 and P4, are utilized as lighting emitters for organic light-emitting diodes (OLEDs), affording promising green and red luminescence with 0.07% and 0.14% of maximum external quantum efficiency, respectively, based on a device with an architecture of ITO/PEDOT:PSS/PTAA/the polymer emitting layer/TPBi/LiF/Al.

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Conjugated Polymers Based on a New Building Block: Dithienophthalimide

Macromolecules ◽

10.1021/ma2003097 ◽

2011 ◽

Vol 44 (11) ◽

pp. 4213-4221 ◽

Cited By ~ 25

Author(s):

Haifeng Wang ◽

Qinqin Shi ◽

Yuze Lin ◽

Haijun Fan ◽

Pei Cheng ◽

...

Keyword(s):

Conjugated Polymers ◽

Building Block

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Bioelectrocatalytic hydrogels from electron-conducting metallopolypeptides coassembled with bifunctional enzymatic building blocks

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.0805249105 ◽

2008 ◽

Vol 105 (40) ◽

pp. 15275-15280 ◽

Cited By ~ 56

Author(s):

Ian R. Wheeldon ◽

Joshua W. Gallaway ◽

Scott Calabrese Barton ◽

Scott Banta

Keyword(s):

Polyphenol Oxidase ◽

Building Block ◽

Leucine Zipper ◽

Electrical Contact ◽

Building Blocks ◽

Coiled Coils ◽

Biofuel Cell ◽

Random Coil ◽

Catalytic Current ◽

And Function

Here, we present two bifunctional protein building blocks that coassemble to form a bioelectrocatalytic hydrogel that catalyzes the reduction of dioxygen to water. One building block, a metallopolypeptide based on a previously designed triblock polypeptide, is electron-conducting. A second building block is a chimera of artificial α-helical leucine zipper and random coil domains fused to a polyphenol oxidase, small laccase (SLAC). The metallopolypeptide has a helix–random-helix secondary structure and forms a hydrogel via tetrameric coiled coils. The helical and random domains are identical to those fused to the polyphenol oxidase. Electron-conducting functionality is derived from the divalent attachment of an osmium bis-bipyrdine complex to histidine residues within the peptide. Attachment of the osmium moiety is demonstrated by mass spectroscopy (MS-MALDI-TOF) and cyclic voltammetry. The structure and function of the α-helical domains are confirmed by circular dichroism spectroscopy and by rheological measurements. The metallopolypeptide shows the ability to make electrical contact to a solid-state electrode and to the redox centers of modified SLAC. Neat samples of the modified SLAC form hydrogels, indicating that the fused α-helical domain functions as a physical cross-linker. The fusion does not disrupt dimer formation, a necessity for catalytic activity. Mixtures of the two building blocks coassemble to form a continuous supramolecular hydrogel that, when polarized, generates a catalytic current in the presence of oxygen. The specific application of the system is a biofuel cell cathode, but this protein-engineering approach to advanced functional hydrogel design is general and broadly applicable to biocatalytic, biosensing, and tissue-engineering applications.

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Fe@B6H6 Aggregates: From Simple Building Blocks to Graphene Analogue

10.21203/rs.3.rs-485747/v1 ◽

2021 ◽

Author(s):

Chao Wang ◽

Jianhua Hou ◽

Qian Duan

Keyword(s):

Building Block ◽

Building Blocks ◽

Electron Structure ◽

Chemical Doping ◽

Hole Density ◽

Hexagonal Hole

Abstract We suggest the possibility to build graphene analogue with the planar hexacoordinate wheel-type Fe@B6H6 cluster as the building block through studying theoretically the geometry, stability and electron structure of its dimer and trimer as well as the dimerization of the two trimers. Employing the dehydrogenation route to polymerization, we can obtain the hexagonal boron sheet that are partly and uniformly filled by Fe atoms in the center of the holes, achieving uniform chemical doping and a very large hexagonal-hole-density. Thus, we may offer a novel cluster-assembled material for experimental chemists to construct graphene analogue.

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