Rapid Synthesis of Primary Amines from Ketones using Choline Chloride/Urea Deep Eutectic as a Reaction Medium

Author(s):  
Cleverton de S. Fernandes ◽  
Camila B. Francisco ◽  
Gisele de F. Gauze ◽  
Roberto Rittner ◽  
Ernani A. Basso
2016 ◽  
Vol 52 (22) ◽  
pp. 4215-4218 ◽  
Author(s):  
D. E. Crawford ◽  
L. A. Wright ◽  
S. L. James ◽  
A. P. Abbott

Mechanochemical synthesis has been applied to the rapid synthesis of Deep Eutectic Solvents (DESs), including Reline 200 (choline chloride : urea, 1 : 2), in a continuous flow methodology by Twin Screw Extrusion (TSE).


2021 ◽  
Author(s):  
xiongchao Lin ◽  
Sasha Yang ◽  
Xiaojia Li ◽  
Caihong Wang ◽  
Yonggang Wang

Abstract In this study, a facile and rapid synthesis approach for SSZ-13 catalyst was proposed using choline chloride (CC) as template. The optimal synthesis condition was explored, and the catalytic performance for methanol-to-olefins (MTO) was examined. Results revealed that the appropriate ratio of soft template could meet the condition for rapid and ordered growth of catalyst crystals. Using environmentally friend and cheaper CC as template could greatly accelerate the formation of bi-hexagonal ring structure in SSZ-13 framework, and it could shorten the synthesis cycle to within 4 h. With a proper amount of CC addition (i.e., m(CC)/m(SiO2) = 0.14), uniform and homogeneously distributed cubic SSZ-13 crystals were obtained with relatively lower aggregation. The catalyst synthesized with m(CC)/m(SiO2)=0.14 demonstrated excellent porous features with a total specific surface area and mesopore volume of 641.706 m2.g-1 and 0.0377 cm3.g-1, respectively. The optimized strong and weak acid sites on the SSZ-13 were obtained by regulating the m(CC)/m(SiO2). As a typical acid catalytic reaction, the SSZ-13 catalyst with strong and weak acid sites exhibited bi-functional role. The lower amount of strong acid sites and larger amount of weak acid sites in the synthesized catalyst were conducive to the catalytic performance for MTO under relatively lower reaction temperature (450 oC). Consequently, the synthesized SSZ-13 showed a better conversion rate and lifetime than that of purchased one. The methanol conversion rate using synthesized catalyst was maintained over 95% within 120 min, and its lifetime was achieved to 172 min. The appropriate acidity and well-developed pore structure of synthesized SSZ-13 could slow down the carbon deposition rate and significantly increase the lifetime of the catalyst. Moreover, the initial selectivity of light olefin could maintain above 50% within 160 min. Eventually, the desirable features of synthesized SSZ-13 catalyst were thought be with good potential for industrial application.


Catalysts ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 655
Author(s):  
Chiara Allegretti ◽  
Francesco G. Gatti ◽  
Stefano Marzorati ◽  
Letizia Anna Maria Rossato ◽  
Stefano Serra ◽  
...  

The use of Reactive Deep Eutectic Solvents (RDESs) in the preparation of polar head modified phospholipids (PLs) with phospholipase D (PLD)-catalyzed biotransformations has been investigated. Natural phosphatidylcholine (PC) has been submitted to PLD-catalyzed transphosphatidylations using a new reaction medium composed by a mixture of RDES/buffer. Instead of exploiting deep eutectic solvents conventionally, just as the reaction media, these solvents have been designed here in order to contribute actively to the synthetic processes by participating as reagents. RDESs were prepared using choline chloride or trimethyl glycine as hydrogen-bond acceptors and glycerol or ethylene glycol, as hydrogen-bond donors as well as nucleophiles for choline substitution. Specifically designed RDES/buffer reaction media allowed the obtainment of PLs with optimized yields in the perspective of a sustainable process implementation.


2020 ◽  
Vol 49 (4) ◽  
pp. 325-330
Author(s):  
Amruta Joglekar-Athavale ◽  
Ganapti S. Shankarling

Purpose This paper aims to propose a simple, effective and environmentally benign method for the synthesis of commercially important pigment copper phthalocyanine (PC) blue has been developed using deep eutectic solvent (DES). Design/methodology/approach DES prepared from choline chloride and urea is used as a reaction medium, as well as a source of ammonia. The design of the experiment and factorial design study has proved that the milder reaction conditions with high yields and reusability of DES are the key features of the present study. Findings The synthesized pigment is obtained at milder reaction conditions with excellent yield, which can be seen from the design of experiments done for the optimization of results. Practical implications The synthesized pigment was used as a colorant in epoxy-based paint and in screen ink, which gave satisfactory results with respect to color values and stability. Social implications The screen ink prepared was formulated considering environmental aspects to avoid the use of solvents. Biodegradable components were added to the colorant to make the ink environment friendly. Originality/value Reactions occur at moderate temperatures without affecting the time factor, thus, it saves energy. A simple, effective and environmentally benign method for the synthesis of commercially important copper PC has been developed using DES. After the first batch, DES synthesized can be reused as a reaction medium where only a stoichiometric amount of urea is to be added. Simple work up, high yield and purity are achieved.


2021 ◽  
Vol 07 ◽  
Author(s):  
Ling Xu ◽  
Wei-Hong Zhang ◽  
Zhen-Shui Cui ◽  
Zhan-Hui Zhang

Objective: 3,3-Disubstituted indol-2-one derivatives have wider applications in pharmaceuticals and they are key intermediates for the synthesis of many kinds of drug candidates. The development of an efficient and practical method to prepare this class of compound is highly desirable from both environmental and economical points of views. Methods: In order to establish an effective synthetic method for preparing 3,3-disubstituted indol-2-one derivatives, the bis-condensation reaction of isatin and 1H-indene-1,3(2H)-dione was selected as a model reaction. A variety of natural deep eutectic solvent (NADES) were prepared and used for this reaction. The generality and limitation of the established method were also investigated. Results: It was found that model reaction can be carried out in natural deep eutectic solvent (NADES) based on choline chloride (ChCl) at 80 oC under microwave irradiation. This protocol with a broad substrate applicability afforded various 2,2'-(2-oxoindoline-3,3-diyl)bis(1H-indene-1,3(2H)-dione) derivatives in high yields. Conclusion: simple and efficient procedure has been developed for synthesis of 2,2'-(2-oxoindoline-3,3-diyl)bis(1H-indene-1,3(2H)-dione), spiro[indoline-3,7'-pyrano[5,6-c:5,6-c']dichromene]-2,6',8'-trione, and spiro[indoline-3,9'-xan-thene] trione via bis-condensation between isatin with 1,3-indandione, 4-hydroxycoumarin or 1,3-cyclohexanedione in nat-ural deep eutectic solvent (NADES) based on choline chloride (ChCl) and glycerol (Gl) under microwave irradiation. The salient features of this protocol are avoidance of any additive/catalyst and toxic organic solvent, clean reaction profiles, non-chromatographic purification procedure, and high to excellent yield. Furthermore, the use of NADES as green reaction medium reduces burden on environment and makes the present method environmentally sustainable.


1970 ◽  
Vol 18 (6) ◽  
pp. 424-438 ◽  
Author(s):  
P. H. STAPLE

Over the range pH 5.6-9.4, the presence of KCl or other common metallic chlorides in excess of 0.1 M in 0.05% solutions of Biebrich scarlet or acid fuchsin produced a colored precipitate within 24 hr. Within the same period, over the range pH 2-7, no precipitate resulted when up to 5 M choline chloride (highest concentration tested) was present in 0.01% solutions of these and other anionic dyes used for staining tissue sections. In paraffin sections of frozen-dried tissues, previously exposed to modified Newcomer's fluid or cyanuric chloride in anhydrous reaction medium, equilibrium staining in the presence of increasing concentrations of choline chloride or potassium chloride was investigated at pH 2.28-2.70, 5.6 and 6.18-6.70 using 0.01% or 0.001% solutions of acid fuchsin, Biebrich scarlet or its isomer crocein scarlet, fast green FCF, naphthol yellow S. The tissues studied were: prevertebral structures included in a horizontal section through the cervical region of a mouse, rat abdominal skin and gingiva, human gingiva. In general, increasing salt concentration progressively inhibited staining, but over a limited range could increase staining, e. g., in cartilage, by unmasking additional dye-binding groups through the dissociation of macromolecular polyionic complexes. Sequential staining with the same or two different dyes in presence of different salt concentrations showed that inhibition of straining by salt was not due to elution of reactive material from sections but to competition between salt and dye anions for cationic sites in tissues. The biologic polyanions heparinate and hyaluronate were found to compete with Biebrich scarlet for tissue cationic sites. The concept of critical electrolyte concentration (CEC) proposed for staining with cationic dyes in salt solutions was found to be applicable to staining with anionic dyes and thus to be generally valid for staining that involves polar interactions. Rat gingival keratin, previously shown to have only a low CEC for the cationic dye Alcian Blue, displayed a high CEC for all of the anionic dyes investigated. Some sites in mouse arterial wall and laryngeal cartilage known to have a high CEC for Alcian Blue showed high CEC for Biebrich scarlet. It is suggested that the high CEC of human gingival parakeratin for anionic dyes depends on the presence of arginine, histidine and lysine protein residues and those few α-amino groups capable of protonation.


Molecules ◽  
2019 ◽  
Vol 24 (4) ◽  
pp. 792 ◽  
Author(s):  
Yerko Fredes ◽  
Lesly Chamorro ◽  
Zaida Cabrera

The effects of the reaction medium and substrate concentration were studied on the selectivity of Novozym 435 using the asymmetric hydrolysis of dimethyl-3-phenylglutarate as a model reaction. Results show that the use of choline chloride ChCl:urea/phosphate buffer 50% (v/v) as a reaction medium increased the selectivity of Novozym 435 by 16% (e.e = 88%) with respect to the one in 100% phosphate buffer (e.e = 76%). Best results were obtained when high substrate concentrations (well above the solubility limit, 27-fold) and ChCl:urea/phosphate buffer 50% (v/v) as reaction medium at pH 7 and 30 °C were used. Under such conditions, the R-monoester was produced with an enantiomeric purity of 99%. Novozym 435 was more stable in ChCl:urea/phosphate buffer 50% (v/v) than in phosphate buffer, retaining a 50% of its initial activity after 27 h of incubation at pH 7 and 40 °C. Results suggest that the use of deep eutectic solvents (ChCl:urea/phosphate buffer) in an heterogeneous reaction system (high substrate concentration) is a viable and promising strategy for the synthesis of chiral drugs from highly hydrophobic substrates.


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