scholarly journals Green resins from renewable resources

Author(s):  
Justin J. Kosalka

This work was aimed at exploring bio-based materials for the purpose of toner production on an industrial scale. Polyester and polyether based resins were prepared in good yields from naturally occurring phenolic compounds with desired thermal and physical properties. Phenols with varying functionality such as guaiacol, eugenol and vanillin along with two synthetically produced phenolic compounds modelling the β-O-4 linkage found in softwood lignins were explored as suitable precursors to synthetic, "green", resins. Phenols were transformed into diols using glycerine carbonate and a base catalyzed reaction. Diols were then polymerized with dicarboxylic acids in an acid catalyzed, transesterfication, reaction. A novel, bio-based polyether was synthesized in one pot, one step polymerization using vanillin. Thermal properties ((Tg) and (Ts) of resulting resins were evaluated. Resulting compounds and polymers were characterized using 1H and 13C NMR spectroscopy, high resolution mass spectrometry, elemental analysis, X-ray crystallography, DSC and GPC.

2021 ◽  
Author(s):  
Justin J. Kosalka

This work was aimed at exploring bio-based materials for the purpose of toner production on an industrial scale. Polyester and polyether based resins were prepared in good yields from naturally occurring phenolic compounds with desired thermal and physical properties. Phenols with varying functionality such as guaiacol, eugenol and vanillin along with two synthetically produced phenolic compounds modelling the β-O-4 linkage found in softwood lignins were explored as suitable precursors to synthetic, "green", resins. Phenols were transformed into diols using glycerine carbonate and a base catalyzed reaction. Diols were then polymerized with dicarboxylic acids in an acid catalyzed, transesterfication, reaction. A novel, bio-based polyether was synthesized in one pot, one step polymerization using vanillin. Thermal properties ((Tg) and (Ts) of resulting resins were evaluated. Resulting compounds and polymers were characterized using 1H and 13C NMR spectroscopy, high resolution mass spectrometry, elemental analysis, X-ray crystallography, DSC and GPC.


2018 ◽  
Vol 15 (7) ◽  
pp. 989-994 ◽  
Author(s):  
Ling Li ◽  
Bo Su ◽  
Yuxiu Liu ◽  
Qingmin Wang

Aim and Objective: During the investigation of sodium nitrite-catalyzed oxidative coupling reaction of aryls, an unprecedented C(sp2)-H and C(sp3)-H coupling of substituted 2-aryl acetonitrile was found. Materials and Methods: The structure of the coupled product was confirmed by 1H and 13C NMR spectroscopy and high-resolution mass spectrometry (HRMS), and comparison of its derivatives with known compounds. The effects of methoxy group in the benzene ring on the reaction were evaluated. Results: The optimized reaction conditions are summarized as follows: CF3SO3H/substrate = 1.5 equiv., NaNO2/substrate = 0.3 equiv., CH3CN as solvent. 2-(4-Methoxyphenyl)acetonitrile and 2-(3,4,5- trimethoxyphenyl)acetonitrile could also generate C(sp2)-H and C(sp3)-H coupling. The coupling reaction occurred as a typical radial mechanism. Conclusion: An unprecedented cyano-induced, NaNO2-catalyzed oxidative C(sp3)-H and C(sp2)-H coupling was reported. The reaction proceeded under very mild conditions, using O2 in the air as terminal oxidant. The unique oxidative manner might provide more inspiration for the development of intriguing oxidative coupling reactions.


Molbank ◽  
10.3390/m1140 ◽  
2020 ◽  
Vol 2020 (2) ◽  
pp. M1140
Author(s):  
Jack Bennett ◽  
Paul Murphy

(2S,3R,6R)-2-[(R)-1-Hydroxyallyl]-4,4-dimethoxy-6-methyltetrahydro-2H-pyran-3-ol was isolated in 18% after treating the glucose derived (5R,6S,7R)-5,6,7-tris[(triethylsilyl)oxy]nona-1,8-dien-4-one with (1S)-(+)-10-camphorsulfonic acid (CSA). The one-pot formation of the title compound involved triethylsilyl (TES) removal, alkene isomerization, intramolecular conjugate addition and ketal formation. The compound was characterized by 1H and 13C NMR spectroscopy, ESI mass spectrometry and IR spectroscopy. NMR spectroscopy was used to establish the product structure, including the conformation of its tetrahydropyran ring.


2016 ◽  
Vol 69 (5) ◽  
pp. 489 ◽  
Author(s):  
Sreedhar V. Kumar ◽  
Warrick K. C. Lo ◽  
Heather J. L. Brooks ◽  
Lyall R. Hanton ◽  
James D. Crowley

A family of mono- and di-fac-rhenium tricarbonyl 2-pyridyl-1,2,3-triazole complexes with different aliphatic and aromatic substituents was synthesized in good-to-excellent yields (46–99 %). The complexes were characterized by 1H and 13C NMR spectroscopy, infrared spectroscopy, electronic (UV-visible) spectroscopy, high-resolution electrospray mass spectrometry, and elemental analyses. In four examples, the solid-state structures of the rhenium(i) complexes were confirmed by X-ray crystallography. The family of the mono- and di-rhenium(i) complexes and the corresponding 2-pyridyl-1,2,3-triazole was tested for antimicrobial activity in vitro against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) microorganisms. Agar-based disk diffusion assays indicated that most of the rhenium(i) complexes were active against Staphylococcus aureus and that the cationic rhenium(i) complexes were more active than the related neutral systems. However, in all cases, the minimum inhibitory concentrations for all the complexes were modest (i.e. 16–1024 µg mL–1).


2020 ◽  
Vol 92 (4) ◽  
pp. 511-517
Author(s):  
Mario Komar ◽  
Maja Molnar ◽  
Anastazija Konjarević

In this study, two fast and efficient protocols for green synthesis of 3-substituted quinazolinones were perfomed. A synthesis of 2-methyl-3-substituted quinazolinones was performed in natural deep eutectic solvents, while 3-aryl quinazolinones were obtained by using microwave assisted synthesis. Benzoxazinone, which was used as an intermediate in the synthesis of 2-methyl-3-substituted quinazolinones, was prepared conventionally from anthranilic acid and acetic anhydride. In order to find the most appropriate synthetic path, twenty natural deep eutectic solvents were applied as a solvent in these syntheses. Choline chloride:urea (1 : 2) was found to be the most efficient solvent and was further used in the synthesis of 2-methyl quinazolinone derivatives (2–12). 3-Aryl quinazolinones (13–17), on the other hand, were synthesized in one-pot microwave-assisted reaction of anthranilic acid, different amines and trimethyl orthoformate. All compounds were synthesized in good to excellent yields, characterized by LC-MS/MS spectrometry and 1H- and 13C-NMR spectroscopy.


2010 ◽  
Vol 75 (8) ◽  
pp. 1033-1040 ◽  
Author(s):  
Vijay Dabholkar ◽  
Dilip Ravi

A simple and efficient method has been developed for the synthesis of 2,4,7-tri(substituted)phenyl-2,4,8,10-tetraza-3,9-dithioxo-5- oxobicyclo[4.4.0]dec-1(6)-ene (4) and 2,4,7-tri(substituted)phenyl- 2,4,8,10-tetraza-3-thioxo-5,9-dioxobicyclo[4.4.0]dec-1(6)-ene (5), by a one-pot, three-component cyclocondensation reaction of a 1,3 dicarbonyl compound (thiobarbituric acid), an aromatic aldehyde, and urea/thiourea using catalytic a amount of concentrated HCl in refluxing ethanol. Representative samples were screened for their anti-microbial activity against the gram-negative bacteria, Escherichia coli and Proteus aeruginosa, and the gram-positive bacteria, Staphyllococcus aureus, and Corynebacterium diphtheriae using the disc diffusion method. The structures of the products were confirmed by IR, 1H- and 13C-NMR spectroscopy, as well as by elemental analysis.


Molbank ◽  
10.3390/m1088 ◽  
2019 ◽  
Vol 2019 (4) ◽  
pp. M1088
Author(s):  
Adel Zamri ◽  
Hilwan Y. Teruna ◽  
Sri Wulansari ◽  
Noval Herfindo ◽  
Neni Frimayanti ◽  
...  

A new analogue of fluorinated pyrazoline (compound 1) has been synthesized via one-pot three-component reaction in a sealed-vessel reactor, Monowave 50. The structure of compound 1 has been established by spectroscopy analysis, including UV, FT-IR, HRMS, 1H and 13C NMR spectroscopy. Based on the in silico studies, this compound showed a good potential as an inhibitor for dengue virus type 2 (DEN2) NS2B/NS3 serine protease and can be used as a reference in the next design of an antidengue virus.


Sign in / Sign up

Export Citation Format

Share Document