Sustainable Esterification of a Soda Lignin with Phloretic Acid

In this work, a sustainable chemical process was developed through the Fischer esterification of Protobind® lignin, a wheat straw soda lignin, and phloretic acid, a naturally occurring phenolic acid. It aimed at increasing the reactivity of lignin by enhancing the number of unsubstituted phenolic groups via a green and solvent-free chemical pathway. The structural features of the technical and esterified lignins were characterized by complementary spectroscopic techniques, including 1H, 13C, 31P, and two-dimensional analysis. A substantial increase in p-hydroxyphenyl units was measured (+64%, corresponding to an increase of +1.3 mmol g−1). A full factorial design of the experiment was employed to quantify the impact of critical variables on the conversion yield. The subsequent statistical analysis suggested that the initial molar ratio between the two precursors was the factor predominating the yield of the reaction. Hansen solubility parameters of both the technical and esterified lignins were determined by solubility assays in multiple solvents, evidencing their high solubility in common organic solvents. The esterified lignin demonstrated a better thermal stability as the onset of thermal degradation shifted from 157 to 220 °C, concomitantly to the shift of the glass transition from 92 to 112 °C. In conclusion, the esterified lignin showed potential for being used as sustainable building blocks for composite and thermoset applications.

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Multifunctional Aromatic Carboxylic Acids as Versatile Building Blocks for Hydrothermal Design of Coordination Polymers

Crystals ◽

10.3390/cryst8020083 ◽

2018 ◽

Vol 8 (2) ◽

pp. 83 ◽

Cited By ~ 58

Author(s):

Jinzhong Gu ◽

Min Wen ◽

Xiaoxiao Liang ◽

Zifa Shi ◽

Marina Kirillova ◽

...

Keyword(s):

Carboxylic Acids ◽

Coordination Polymers ◽

Crystal Engineering ◽

Building Blocks ◽

Structural Features ◽

Molar Ratio ◽

Hydrothermal Conditions ◽

Polycarboxylic Acids ◽

Sensing Applications ◽

Metal Organic

Selected recent examples of coordination polymers (CPs) or metal-organic frameworks (MOFs) constructed from different multifunctional carboxylic acids with phenyl-pyridine or biphenyl cores have been discussed. Despite being still little explored in crystal engineering research, such types of semi-rigid, thermally stable, multifunctional and versatile carboxylic acid building blocks have become very promising toward the hydrothermal synthesis of metal-organic architectures possessing distinct structural features, topologies, and functional properties. Thus, the main aim of this mini-review has been to motivate further research toward the synthesis and application of coordination polymers assembled from polycarboxylic acids with phenyl-pyridine or biphenyl cores. The importance of different reaction parameters and hydrothermal conditions on the generation and structural types of CPs or MOFs has also been highlighted. The influence of the type of main di- or tricarboxylate ligand, nature of metal node, stoichiometry and molar ratio of reagents, temperature, and presence of auxiliary ligands or templates has been showcased. Selected examples of highly porous or luminescent CPs, compounds with unusual magnetic properties, and frameworks for selective sensing applications have been described.

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Constructing well-being from hedonic building blocks: Evidence that depression distorts the impact of daily pleasure and pain

PsycEXTRA Dataset ◽

10.1037/e529412014-209 ◽

2005 ◽

Author(s):

Michael F. Steger ◽

Todd B. Kashdan ◽

Shigehiro Oishi

Keyword(s):

Well Being ◽

Building Blocks ◽

The Impact

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Mechanically-Tunable Quantum Interference in Ferrocene-Based Single-Molecule Junctions

10.26434/chemrxiv.12252059 ◽

2020 ◽

Author(s):

María Camarasa-Gómez ◽

Daniel Hernangómez-Pérez ◽

Michael S. Inkpen ◽

Giacomo Lovat ◽

E-Dean Fung ◽

...

Keyword(s):

Single Molecule ◽

Quantum Interference ◽

Degrees Of Freedom ◽

Building Blocks ◽

Ferrocene Derivative ◽

Single Molecule Junctions ◽

Molecule Junction ◽

Single Molecule Junction ◽

The Impact ◽

D Orbitals

Ferrocenes are ubiquitous organometallic building blocks that comprise a Fe atom sandwiched between two cyclopentadienyl (Cp) rings that rotate freely at room temperature. Of widespread interest in fundamental studies and real-world applications, they have also attracted some interest as functional elements of molecular-scale devices. Here we investigate the impact of the configurational degrees of freedom of a ferrocene derivative on its single-molecule junction conductance. Measurements indicate that the conductance of the ferrocene derivative, which is suppressed by two orders of magnitude as compared to a fully conjugated analog, can be modulated by altering the junction configuration. Ab initio transport calculations show that the low conductance is a consequence of destructive quantum interference effects that arise from the hybridization of metal-based d-orbitals and the ligand-based π-system. By rotating the Cp rings, the hybridization, and thus the quantum interference, can be mechanically controlled, resulting in a conductance modulation that is seen experimentally.

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A Pseudo Five-Fold Symmetrical Ligand Drives Geometric Frustration in Porous Metal-Organic and Hydrogen Bonded Frameworks

10.26434/chemrxiv.12098142.v1 ◽

2020 ◽

Author(s):

Frederik Haase ◽

Gavin Craig ◽

Mickaele Bonneau ◽

kunihisa sugimoto ◽

Shuhei Furukawa

Keyword(s):

Topological Defects ◽

Porous Metal ◽

Building Blocks ◽

Structural Features ◽

Equilibrium Structure ◽

Sorption Behavior ◽

Building Unit ◽

Geometric Frustration ◽

Secondary Building Units ◽

Hydrogen Bonded

Reticular framework materials thrive on designability, but unexpected reaction outcomes are crucial in exploring new structures and functionalities. By combining “incompatible” building blocks, we employed geometric frustration in reticular materials leading to emergent structural features. The combination of a pseudo C5 symmetrical organic building unit based on a pyrrole core, with a C4 symmetrical copper paddlewheel synthon led to three distinct frameworks by tuning the synthetic conditions. The frameworks show structural features typical for geometric frustration: self-limiting assembly, internally stressed equilibrium structures and topological defects in the equilibrium structure, which manifested in the formation of a hydrogen bonded framework, distorted and broken secondary building units and dangling functional groups, respectively. The influence of geometric frustration on the CO2 sorption behavior and the discovery of a new secondary building unit shows geometric frustration can serve as a strategy to obtain highly complex porous frameworks.

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A Pseudo Five-Fold Symmetrical Ligand Drives Geometric Frustration in Porous Metal-Organic and Hydrogen Bonded Frameworks

10.26434/chemrxiv.12098142 ◽

2020 ◽

Author(s):

Frederik Haase ◽

Gavin Craig ◽

Mickaele Bonneau ◽

kunihisa sugimoto ◽

Shuhei Furukawa

Keyword(s):

Topological Defects ◽

Porous Metal ◽

Building Blocks ◽

Structural Features ◽

Equilibrium Structure ◽

Sorption Behavior ◽

Building Unit ◽

Geometric Frustration ◽

Secondary Building Units ◽

Hydrogen Bonded

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Insulating Composites Made from Sulfur, Canola Oil, and Wool

10.26434/chemrxiv.13464842.v1 ◽

2020 ◽

Author(s):

Israa Bu Najmah ◽

Nicholas Lundquist ◽

Melissa K. Stanfield ◽

Filip Stojcevski ◽

Jonathan A. Campbell ◽

...

Keyword(s):

Tensile Strength ◽

Canola Oil ◽

Building Blocks ◽

Atom Economy ◽

Flame Resistance ◽

Sustainable Building ◽

Second Stage ◽

Wool Fibers ◽

Insulating Properties ◽

Polysulfide Polymer

An insulating composite was made from the sustainable building blocks wool, sulfur, and canola oil. In the first stage of the synthesis, inverse vulcanization was used to make a polysulfide polymer from the canola oil triglyceride and sulfur. This polymerization benefits from complete atom economy. In the second stage, the powdered polymer is mixed with wool, coating the fibers through electrostatic attraction. The polymer and wool mixture is then compressed with mild heating to provoke S-S metathesis in the polymer, which locks the wool in the polymer matrix. The wool fibers impart tensile strength, insulating properties, and flame resistance to the composite. All building blocks are sustainable or derived from waste and the composite is a promising lead on next-generation insulation for energy conservation.

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Model Pembelajaran Teams Games Tournaments (TGT) untuk Meningkatkan Hasil Belajar Siswa

PHILANTHROPY Journal of Psychology ◽

10.26623/philanthropy.v3i2.1622 ◽

2019 ◽

Vol 3 (2) ◽

pp. 110

Author(s):

Suwarno Suwarno

Keyword(s):

Social Capital ◽

Academic Success ◽

Service Learning ◽

Learning Outcomes ◽

School Effectiveness ◽

Social Trust ◽

Building Blocks ◽

Learning Model ◽

Committee Report ◽

The Impact

Abstract. This study aims to determine the effectiveness of the Teams Games Tournament (TGT) learning model to improve student learning outcomes. This research is important because the lecture learning model makes learning meaningless so it impacts on low learning outcomes. This research uses quasi experiment using control class and experimental class. Respondents in this study were students of class X SMK 8 Semarang Academic Year 2017/2018. Sample selection using random sampling, class X1 is used as a control class and X2 is an experimental class. The experimental class was given an intervention by learning Teams Games Tournaments (TGT), while the control class used lecture learning. The effectiveness of the model was measured by the student test analysis method. then analyzed by completeness test and average difference test. The findings of this study are the learning outcomes of experimental class students achieving better learning outcomes than classes using the lecture method.Keywords: Learning Model, Teams Games Tournaments (TGT). Students Daftar Pustaka Bofota, Y. B., & Bofota, Y. B. (2017). The impact of social capital on children educational outcomes : the case of Tanzania The impact of social capital on children educational outcomes : The case of Tanzania.Cahuc, P., Shleifer, A., & Algan, Y. (2014). Teaching Practices and Social Capital. (6052).Catts, R., & Ozga, J. (2015). What is Social Capital and how might it be used in Scotland ’ s Schools ? (36).Flint, N. (2017). Full report Schools , communities and social capital : building blocks in the ’ Big Society ’ Contents.Goddard, R. D. (2016). Relational Networks , Social Trust , and Norms : A Social Capital Perspective on Students ’ Chances of Academic Success. 25(1), 59–74.Eddy Prasongko, 2017. Team Game Tournament. Bandung. Jawa BaratEndang Poerwanti, dkk. 2008. Asesmen Pembelajaran SD. Jakarta: Direktorat Jendral Pendidikan Tinggi Departemen Pendidikan NasionalHargreaves, A. (2015). School Social Capital and School Effectiveness. 37, 119–136.Kurnia, Inggridwati. dkk. 2018. Perkembangan belajar peserta didik. Jakarta: Direktorat Jendral Pendidikan Tinggi Departemen Pendidikan NasionalPurwanto. M Ngalim. 2015. Psikologi Pendidikan. Bandung: PT Remaja RosdakaryaSiddiq, M. Djauhar. 2018. Pengembangan Bahan Pembelajaran SD. Jakarta: Direktorat Jendral Pendidikan Tinggi Departemen Pendidikan Nasional.Sugiyono, 2005. Metode Penelitian Kuantitatif, Kualitatif dan Rn D, Bandung AftabetaLash, D., & Belfiore, G. (2017). 5 Essentials in Building Social Capital Report 4 of the MyWays Student Success Series. (October).Mikiewicz, P., Jonasson, J. T., Gudmundsson, G., Blondal, K. S., & Korczewska, D. M. (2011). Comparative research between Poland and Iceland.Schlesselman, L., Borrego, M., Bloom, T. J., Mehta, B., Drobitch, R. K., & Smith, T. (2015). An Assessment Of Service-Learning In 34 US Schools Of Pharmacy Follow Up On The 2001 Professional Affairs Committee Report. American Journal of Pharmaceutical Education, 79(8). https://doi.org/10.5688/ajpe798116

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Using Hansen Solubility Parameters To Reduce Permeation In Clay

10.31988/scitrends.22503 ◽

2018 ◽

Author(s):

Michael Huth

Keyword(s):

Solubility Parameters ◽

Hansen Solubility Parameters ◽

Hansen Solubility

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Development of Strategies for Glycopeptide Synthesis: An Overview on the Glycosidic Linkage

Current Organic Chemistry ◽

10.2174/1385272824999200701121037 ◽

2020 ◽

Vol 24 (21) ◽

pp. 2475-2497

Author(s):

Andrea Verónica Rodríguez-Mayor ◽

German Jesid Peralta-Camacho ◽

Karen Johanna Cárdenas-Martínez ◽

Javier Eduardo García-Castañeda

Keyword(s):

Chemical Synthesis ◽

Solid Phase ◽

Building Blocks ◽

Heterogeneous Environments ◽

Phase Synthesis ◽

Low Concentrations ◽

Biological Sources ◽

Synthetic Routes ◽

The Impact ◽

Potential Use

Glycoproteins and glycopeptides are an interesting focus of research, because of their potential use as therapeutic agents, since they are related to carbohydrate-carbohydrate, carbohydrate-protein, and carbohydrate-lipid interactions, which are commonly involved in biological processes. It has been established that natural glycoconjugates could be an important source of templates for the design and development of molecules with therapeutic applications. However, isolating large quantities of glycoconjugates from biological sources with the required purity is extremely complex, because these molecules are found in heterogeneous environments and in very low concentrations. As an alternative to solving this problem, the chemical synthesis of glycoconjugates has been developed. In this context, several methods for the synthesis of glycopeptides in solution and/or solid-phase have been reported. In most of these methods, glycosylated amino acid derivatives are used as building blocks for both solution and solid-phase synthesis. The synthetic viability of glycoconjugates is a critical parameter for allowing their use as drugs to mitigate the impact of microbial resistance and/or cancer. However, the chemical synthesis of glycoconjugates is a challenge, because these molecules possess multiple reaction sites and have a very specific stereochemistry. Therefore, it is necessary to design and implement synthetic routes, which may involve various protection schemes but can be stereoselective, environmentally friendly, and high-yielding. This review focuses on glycopeptide synthesis by recapitulating the progress made over the last 15 years.

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Application of Nitrogen Heterocyclic Carbenes in Organocatalysis

Current Catalysis ◽

10.2174/2211544709999201201120617 ◽

2020 ◽

Vol 09 ◽

Author(s):

Minita Ojha ◽

R. K. Bansal

Keyword(s):

Asymmetric Catalysis ◽

Building Blocks ◽

Structural Features ◽

Heterocyclic Carbenes ◽

Stetter Reaction ◽

Metal Pollutants ◽

Synthetic Strategy ◽

Wide Range ◽

Benzoin Condensation ◽

Nitrogen Heterocyclic

Background: During the last two decades, horizon of research in the field of Nitrogen Heterocyclic Carbenes (NHC) has widened remarkably. NHCs have emerged as ubiquitous species having applications in a broad range of fields, including organocatalysis and organometallic chemistry. The NHC-induced non-asymmetric catalysis has turned out to be a really fruitful area of research in recent years. Methods: By manipulating structural features and selecting appropriate substituent groups, it has been possible to control the kinetic and thermodynamic stability of a wide range of NHCs, which can be tolerant to a variety of functional groups and can be used under mild conditions. NHCs are produced by different methods, such as deprotonation of Nalkylhetrocyclic salt, transmetallation, decarboxylation and electrochemical reduction. Results: The NHCs have been used successfully as catalysts for a wide range of reactions making a large number of building blocks and other useful compounds accessible. Some of these reactions are: benzoin condensation, Stetter reaction, Michael reaction, esterification, activation of esters, activation of isocyanides, polymerization, different cycloaddition reactions, isomerization, etc. The present review includes all these examples published during the last 10 years, i.e. from 2010 till date. Conclusion: The NHCs have emerged as versatile and powerful organocatalysts in synthetic organic chemistry. They provide the synthetic strategy which does not burden the environment with metal pollutants and thus fit in the Green Chemistry.

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