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In this work, a class of transition metal-modified MCM-41 mesoporous silica supported ionic liquids nanocatalysts were constructed and efficiently used as catalysts for the effective carboxylation of terminal alkynes through CO2 utilization. The main factors affecting the catalytic performance of carboxylation and its possible reaction mechanism were sufficiently discussed. The results showed that when the dosage was 0.2 g, the temperature was 40°C and the CO2 pressure was 0.3 MPa, the supported catalyst MCM-41@IL-Sm showed the optimal catalytic efficiency. The novel catalyst proved to be highly efficient for the sustainable synthesis of alkynyl carboxylic acids attributing good to excellent yields of 82%–95% within 7–12 h. Moreover, MCM-41@IL-Sm could be recycled and reused six times without noticeable decrease in catalytic activity from two-phase system under external heterogeneous field. The application of supported ionic liquids in the field of carbon dioxide carboxylation has injected a new power source for the efficient and effective production of value-added chemicals from waste CO2. [ABSTRACT FROM AUTHOR]

In this study, we report a successful strategy for the generation of a type of multifunctional heterogeneous supported ionic liquids catalysts. The synthesized supported ionic liquids (Fe‐MCM‐41/IL) were used in the catalytic cyclocondensation of 2‐aminobenzamide and various ketones and aldehydes towards the efficient synthesis of the dihydroquinazolinones under green conditions. The influence of the different catalysts and reaction parameters on the catalytic behaviors were sufficiently investigated. The supported catalyst (2)Fe‐MCM‐41/IL(0.6) showed the optimal catalytic efficiency. A hot filtration experiment revealed that the reaction proceeded in a heterogeneous pathway. The catalytic activity of (2)Fe‐MCM‐41/IL(0.6) could be maintained efficiently after recycling up to five consecutive runs under the optimized reaction conditions. Merits of this meticulously designed protocol are the use of novel supported catalyst, easy work‐up process, feasibility and sustainability, indicating its potential industrial application prospect. [ABSTRACT FROM AUTHOR]

A type of MCM-41 supported dual imidazolium ionic liquids have been synthesized and efficiently used as catalysts in the sustainable chemical conversion of CO2 and epoxides into cyclic carbonates. It was shown that the highest efficiency was achieved in the cycloaddition of a variety of epoxides and CO2 in the presence of the MCM-41@DILSCN solid catalyst under mild conditions. More interestingly, the catalyst was stable, very active, robust, and displayed good recyclability without significant loss of catalytic activity after six consecutive cycles during the process. Overall, the present protocol of synthesizing cyclic carbonates under solvent free conditions using MCM-41@DILSCN is promising for industrial applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Early diagnoses of diseases require us to detection tiny biomarkers. • Nanofluidic devices magnify signal of tiny biomarkers. • Nanofluidic devices hold a promise for in portable sensors and POC detection. Disease diagnosis, especially for early diagnosis, is the most effective method to prevent disease development and mortality. However, low abundance clinical biomarkers in samples pose a challenge to sensitivity and selectivity of early diagnosis. Nanoconfined environment provides unique effects, including ionic current rectification, steric effect, and selective transport, etc., which could be applied to magnify signal and enhance sensitivity in discrimination of biomarkers on electrochemical (EC) sensors. Therefore, nanofluidic EC sensors have experienced a speedy development in ultra-sensitive sensing. In this review, we highlight the application of nanofluidic EC sensors with different structures (nanocapillary, nanoporous membrane, nanopore, and micro/nanofluidic chip) in biomarkers detection. Different types of nanofluidic devices, mechanism of nanoconfined effect, and their applications in ultra-sensitive sensing are summarized and discussed. Finally, this review provides a respective about nanofluidic EC sensors in biomarkers detection and helps the understanding nanoconfined effect for developing new analysis. [ABSTRACT FROM AUTHOR]

Periodic mesoporous organosilica (PMO) supported ionic liquids with high catalytic ability were prepared and tested in synthesis of 2‐oxazolidinones from the three‐component cycloaddition reactions of CO2, aryl amines and epoxide. The functionalized PMO material PMO@TZ‐ILSmCl4 revealed the most excellent catalytic performance than PMO@TZ‐ILLaCl4 during the catalytic synthesis of 2‐oxazolidinones. Different parameters such as catalyst loading, temperature, CO2 pressure and reaction time were also investigated. Good to excellent yields for 2‐oxazolidinones and stable reusability were reached in the CO2 cycloaddition under solvent‐ /ligand‐free conditions. This work provides a useful route to design novel and highly efficient catalytic systems for the transformation of CO2 into other valuable 2‐oxazolidinones. [ABSTRACT FROM AUTHOR]