45 research outputs found
Task Specific Onium Salts and Ionic liquids as Soluble Supports in Grieco's Multicomponent Synthesis of Tetrahydroquinolines
No full textInternational audienc
Functionalization of textiles using eco-friendly sol-gel processes
No full textInternational audienceThe surface functionalization of textile fibers has recently gained much interest for the production of technical and aesthetic textiles with specific properties. Textiles can undergo pre-treatment to gain new functionalities such as antibacterial character, fire-retardancy, water resistance, electrical or magnetic behavior, and so on. Many new pre-treatment processes have been developed thanks to the evolution of nano-technologies and other innovations like jet-ink printing, electrospinning, and sol-gel chemistry, in addition to conventional techniques such as screen-printing and polymer coating. Different methods are used depending on the desired functionality and the final use of the fabric: clothing, technical use, or "smart textile" applications. In our work on functional textiles, we aimed to prepare wearable textiles with special optical effects by the pad-dry-cure method using a novel sol-gel process. This method preserves the mechanical properties of the fabric. A study of this process and its critical parameters was conducted to optimize this promising approach. We found that dyeing by the sol-gel process can be achieved at room temperature and uses fewer solvents and chemicals, making it an eco-friendly process. Additionally, the sol-gel process was employed to prepare a fluorescent textile sensitive to pH variations that can also be observed with the naked eye. This propriety is of use in versatile applications such as the detection of acid rain, body-sweat variations, and medical pads. Furthermore, luminescent molecules were applied to textiles by the sol-gel process [1] along with polymer coating and screen printing. In most cases, fluorescent textiles are used for amusement and decoration purposes, but they can also be used to mark textiles rolls as a sort of encryption against counterfeiting [2]. To this end, "invisible" fluorescent ink was developed and adjusted to be used in hand-writing pens, jet-ink printers, or rubber stamps. As an application of this ink, we printed QR codes on cotton fabric using a jet-ink printer intending to conceal encrypted pieces of information. The printed code appears only under 365nm excitation light and can be scanned to identify and decrypt the code. This invisible marking can be used by industrials to fight against counterfeiting and to protect their trademark. In conclusion, the sol-gel process that we have developed enables the eco-friendly preparation of functional textiles with original optical properties.-[1] BOUKHRISS A, et al. Materials Advances. 2020; 4, 918-925. -[2] FATAHI Z, et al. Journal of Analysis and Testing. 2020; 4, 307-31
ChemInform Abstract: Onium Salt Supported Organic Synthesis in Water: Application to Grieco′s Multicomponent Reaction.
No full textA Simple Chiral Cu(II) Complex as an Effective Phase‐Transfer Catalyst for the Enantioselective Alkylation of Dissymmetric Glycinate Ketimines
No full text
Homogeneous Esterification of Cellulose in the Mixture N-Butylpyridinium Chloride/Dimethylsulfoxide
No full textThe present study deals with the homogeneous acylation of cellulose with p-nitrobenzoyl chloride in a reaction medium composed of a mixture of 1-butylpyridinium chloride and dimethylsulfoxide (BPyCl/DMSO), in the presence of different bases and under mild conditions. The preparation of cellulose p-nitrobenzoate depending on the reaction conditions, the influences of reaction parameters such as the base type, and the types of cellulose (kraft and microcrystalline) on the products were investigated. Cellulose p-nitrobenzoate with a degree of substitution (DS) in the range from 0.12 to 1.5 was accessible, with a low excess of reagent and for a short reaction time. The cellulose esters were characterized by 1H-NMR, 13C NMR, and FT-IR spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and solubility tests
Activation of Bismuth(III) Derivatives in Ionic Liquids: Novel and Recyclable Catalytic Systems for Friedel−Crafts Acylation of Aromatic Compounds
No full textThe activity of four bismuth(III) derivatives when employed as Friedel−Crafts catalysts for the acylation of aromatics was found to increase
dramatically when dissolved in ionic liquids. Solutions of bismuth oxide or triflate in [emim][NTf2] and [bmim][NTf2] are the most efficient
catalytic systems, with catalyst loading as low as 1% leading to clean, high-yielding acylation of a variety of benzene derivatives. These
improved Friedel−Crafts catalytic systems can also be efficiently recycled as opposed to traditional systems
Characterization of the Inclusion of Polymer Membrane for Application as Electrolyte in Direct Methanol Fuel Cell System
No full textSeed quality as a proxy of climate-ready orphan legumes: the need for a multidisciplinary and multi-actor vision
No full textIn developing countries, orphan legumes stand at the forefront in the struggle
against climate change. Their high nutrient value is crucial in malnutrition and
chronic diseases prevention. However, as the ‘orphan’ definition suggests, their
seed systems are still underestimated and seed production is scanty. Seed
priming is an effective, sustainable strategy to boost seed quality in orphan
legumes for which up-to-date guidelines are required to guarantee reliable and
reproducible results. How far are we along this path? What do we expect from
seed priming? This brings to other relevant questions. What is the socioeconomic
relevance of orphan legumes in the Mediterranean Basin? How to
potentiate a broader cultivation in specific regions? The case study of the
BENEFIT-Med (Boosting technologies of orphan legumes towards resilient
farming systems) project, developed by multidisciplinary research networks,
envisions a roadmap for producing new knowledge and innovative technologies to improve seed productivity through priming, with the long-term
objective of promoting sustainability and food security for/in the climatesensitive
regions. This review highlights the existing drawbacks that must be
overcome before orphan legumes could reach the state of ‘climate-ready crops’.
Only by the integration of knowledge in seed biology, technology and agronomy,
the barrier existing between research bench and local agricultural fields may be
overcome, generating high-impact technical innovations for orphan legumes.
We intend to provide a powerful message to encourage future research in line
with the United Nations Agenda 2030 for Sustainable Development
Ethyl 2-amino-4-phenyl-4H-1-benzothieno[3,2-b]pyran-3-carboxylate
No full textThe title heterocyclic compound, C20H17NO3S, was synthesized by condensation of ethyl cyanoacetate with (Z)-2-benzylidenebenzo[b]thiophen-3(2H)-one in the presence of a basic catalyst in ethanol. The phenyl and ester groups make dihedral angles of 77.67 (6) and 8.52 (6)°, respectively, with the benzothienopyran ring system [maximum r.m.s. deviation = 0.1177 (13) Å]. In the crystal, centrosymmetric dimers are formed through pairs of N—H...O hydrogen bonds between the amine and ester groups. Intermolecular C—H...N hydrogen bonds and C—H...π interactions involving the thiophene ring are also observed
