Esterification of cellulose using carboxylic acid-based deep eutectic solvents to produce high-yield cellulose nanofibers

2021 ◽  
Vol 251 ◽  
pp. 117018
Author(s):  
Suling Liu ◽  
Qing Zhang ◽  
Shaheng Gou ◽  
Lili Zhang ◽  
Zhiguo Wang
Keyword(s):  
Carboxylic Acid ◽  
Cellulose Nanofibers ◽  
Deep Eutectic Solvents ◽  
High Yield

scholarly journals Esterifications with 2-(Trimethylsilyl)ethyl 2,2,2-Trichloroacetimidate

Organics ◽  
2021 ◽  
Vol 2 (1) ◽  
pp. 17-25
Author(s):  
Wenhong Lin ◽  
Shea T. Meyer ◽  
Shawn Dormann ◽  
John D. Chisholm
Keyword(s):  
Carboxylic Acid ◽  
High Yield ◽  
Deuterium Labeling ◽  
Ester Formation ◽  
Acid Substrate

2-(Trimethylsilyl)ethyl 2,2,2-trichloroacetimidate is readily synthesized from 2-trimethylsilylethanol in high yield. This imidate is an effective reagent for the formation of 2-trimethylsilylethyl esters without the need for an exogenous promoter or catalyst, as the carboxylic acid substrate is acidic enough to promote ester formation without an additive. A deuterium labeling study indicated that a β-silyl carbocation intermediate is involved in the transformation.

Functional Group Interconversion

2015 ◽  
Author(s):  
Tristan H. Lambert
Keyword(s):  
Carboxylic Acid ◽  
High Yield ◽  
Staudinger Ligation ◽  
University Of Alberta ◽  
University Of Tennessee ◽  
University Of British Columbia ◽  
National University ◽  
Seoul National University ◽  
Oxidative Amidation ◽  
The University

Glenn M. Samm is at the University of British Columbia reported (Angew. Chem. Int. Ed. 2012, 51, 10804) the photofluorodecarboxylation of aryloxyacids such as 1 using Selectfluor 2. Jean-François Paquin at the Université Laval found (Org. Lett. 2012, 14, 5428) that the halogenation of alcohols (e.g., 4 to 5) could be achieved with [Et2NSF2]BF4 (XtalFluor-E) in the presence of the appropriate tetraethylammonium halide. A method for the reductive bromination of carboxylic acid 6 to bromide 7 was developed (Org. Lett. 2012, 14, 4842) by Norio Sakai at the Tokyo University of Science. Professor Sakai also reported (Org. Lett. 2012, 14, 4366) a related method for the reductive coupling of acid 8 with octanethiol to produce thioether 9. The esterification of primary alcohols in water-containing solvent was achieved (Org. Lett. 2012, 14, 4910) by Michio Kurosu at the University of Tennessee Health Science Center using the reagent 11, such as in the conversion of alcohol 10 to produce 12 in high yield. Hosahudya N. Gopi discovered (Chem. Commun. 2012, 48, 7085) that the conversion of thioacid 13 to amide 14 was rapidly promoted by CuSO4. A ruthenium-catalyzed dehydrative amidation procedure using azides and alcohols, such as the reaction of 15 with phenylethanol to produce 16, was reported (Org. Lett. 2012, 14, 6028) by Soon Hyeok Hong at Seoul National University. An alternative oxidative amidation was developed (Tetrahedron Lett. 2012, 53, 6479) by Chengjian Zhu at Nanjing University and the Shanghai Institute of Organic Chemistry who utilized catalytic tetrabutylammonium iodide and disubstituted formamides to convert alcohols such as 17 to amides 18. A redox catalysis strategy was developed (Angew. Chem. Int. Ed. 2012, 51, 12036) by Brandon L. Ashfeld at Notre Dame for the triphenylphosphine-catalyzed Staudinger ligation of carboxylic acid 19 to furnish amide 20. For direct catalytic amidation of carboxylic acids and amines such as in the conversion of 21 to 23, Dennis G. Hall at the University of Alberta reported (J. Org. Chem. 2012, 77, 8386) that the boronic acid 22 was a highly effective catalyst that operated at room temperature.

scholarly journals Integration of renewable deep eutectic solvents with engineered biomass to achieve a closed-loop biorefinery

2019 ◽  
Vol 116 (28) ◽  
pp. 13816-13824 ◽  
Author(s):  
Kwang Ho Kim ◽  
Aymerick Eudes ◽  
Keunhong Jeong ◽  
Chang Geun Yoo ◽  
Chang Soo Kim ◽  
...  
Keyword(s):  
Genetic Engineering ◽  
Closed Loop ◽  
Enzymatic Saccharification ◽  
Cinnamyl Alcohol Dehydrogenase ◽  
Deep Eutectic Solvents ◽  
High Yield ◽  
Cellulosic Biofuels ◽  
Plant Genetic Engineering ◽  
Promising Strategy ◽  
Monolignol Biosynthesis

Despite the enormous potential shown by recent biorefineries, the current bioeconomy still encounters multifaceted challenges. To develop a sustainable biorefinery in the future, multidisciplinary research will be essential to tackle technical difficulties. Herein, we leveraged a known plant genetic engineering approach that results in aldehyde-rich lignin via down-regulation of cinnamyl alcohol dehydrogenase (CAD) and disruption of monolignol biosynthesis. We also report on renewable deep eutectic solvents (DESs) synthesized from phenolic aldehydes that can be obtained fromCADmutant biomass. The transgenicArabidopsis thaliana CADmutant was pretreated with the DESs and showed a twofold increase in the yield of fermentable sugars compared with wild type (WT) upon enzymatic saccharification. Integrated use of low-recalcitrance engineered biomass, characterized by its aldehyde-type lignin subunits, in combination with a DES-based pretreatment, was found to be an effective approach for producing a high yield of sugars typically used for cellulosic biofuels and biobased chemicals. This study demonstrates that integration of renewable DES with plant genetic engineering is a promising strategy in developing a closed-loop process.

scholarly journals The Role of Polyfunctionality in the Formation of [Ch]Cl-Carboxylic Acid-Based Deep Eutectic Solvents

2018 ◽  
Vol 57 (32) ◽  
pp. 11195-11209 ◽  
Author(s):  
Emanuel A. Crespo ◽  
Liliana P. Silva ◽  
Mónia A. R. Martins ◽  
Mark Bülow ◽  
Olga Ferreira ◽  
...  
Keyword(s):  
Carboxylic Acid ◽  
Deep Eutectic Solvents

scholarly journals Preparation of Cellulose Nanofibers from Bagasse by Phosphoric Acid and Hydrogen Peroxide Enables Fibrillation via a Swelling, Hydrolysis, and Oxidation Cooperative Mechanism

Nanomaterials ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 2227
Author(s):  
Jinlong Wang ◽  
Qi Wang ◽  
Yiting Wu ◽  
Feitian Bai ◽  
Haiqi Wang ◽  
...  
Keyword(s):  
Plant Cell ◽  
Cell Walls ◽  
Cellulose Nanofibers ◽  
Oxidative Degradation ◽  
High Yield ◽  
Plant Cell Walls ◽  
Good Thermal Stability ◽  
Mild Conditions ◽  
Natural Cellulose ◽  
High Yields

Due to the natural cellulose encapsulated in both lignin and hemicellulose matrices, as well as in plant cell walls with a compact and complex hierarchy, extracting cellulose nanofibers (CNFs) from lignocellulosic biomass is challenging. In this study, a sustainable high yield strategy with respect to other CNF preparations was developed. The cellulose was liberated from plant cell walls and fibrillated to a 7–22 nm thickness in one bath treatment with H3PO4 and H2O2 under mild conditions. The cellulose underwent swelling, the lignin underwent oxidative degradation, and the hemicellulose and a small amount of cellulose underwent acid hydrolysis. The CNFs’ width was about 12 nm, with high yields (93% and 50% based on cellulose and biomass, respectively), and a 64% crystallinity and good thermal stability were obtained from bagasse. The current work suggests a strategy with simplicity, mild conditions, and cost-effectiveness, which means that this method can contribute to sustainable development for the preparation of CNFs.

β-Carboline-3-carboxylic Acid (9H-Pyrido[3,4-b]indole-3-carboxylic Acid) and Related Compounds

1989 ◽  
Vol 42 (6) ◽  
pp. 813 ◽  
Author(s):  
JA Maclaren
Keyword(s):  
Carboxylic Acid ◽  
Rat Brain ◽  
High Yield ◽  
Brain Membranes ◽  
Novel Synthesis ◽  
Rat Brain Membranes ◽  
Related Compounds ◽  
Relative Inhibition

The synthesis of β-carboline-3-carboxylic acid and its esters (4) by oxidation of the corresponding 1,2,3,4-tetrahydro derivatives (2) or of the 3,4-dihydro derivatives (3) has been studied. A novel synthesis of the esters (3) [and hence of (4)] has been achieved in high yield by cyclization and elimination from the enamine (5). The relative inhibition of binding of a benzodiazepine to rat brain membranes by the esters (2)-(4) has been determined.

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