N-Heterocyclic Carbene Moiety in Highly Porous Organic Hollow Nanofibers for Efficient CO₂ Conversions: A Comparative Experimental and Theoretical Study

ACS Catalysis, Год журнала: 2024, Номер 14(2), С. 718 - 727

Опубликована: Янв. 2, 2024

Global warming and climate change are two severe environmental dangers brought on by the steady rise in carbon dioxide (CO2) concentration atmosphere. Thus, order to reduce this problem, it is essential find an efficient material for high CO2 capture that can simultaneously exhibit good catalytic activity utilization into useful chemicals. Herein, we report synthesis of N-heterocyclic carbene-based porous organic polymers (NHC-01 NHC-02) using Friedel–Crafts reaction with imidazolium salt bi-phenyl. Among polymers, NHC-01 exhibited outstanding stability, flexibility, BET surface area (1298 m2 g–1). displayed a uptake capacity 2.85 mmol g–1 under 1.0 bar pressure at 273 K. NHC-01/02 has been utilized as metal-free organocatalyst conversion due its area, absorption capacity, bears NHC moiety network. selectively reduced methanol via hydrosilylation complete silane atmospheric pressure. Furthermore, catalyst also shows toward N-formylation reductive cyclization reactions, which showed yields up least four cycles. The mechanisms studied theoretical simulation density functional theory (DFT), intermediates have appropriate free energy level promote low barrier.

Язык: Английский

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Automated Transition Metal Catalysts Discovery and Optimisation with AI and Machine Learning

ChemCatChem, Год журнала: 2024, Номер 16(10)

Опубликована: Янв. 5, 2024

Abstract Significant progress has been made in recent years the use of AI and Machine Learning (ML) for catalyst discovery optimisation. The effectiveness ML data science techniques was demonstrated predicting optimising enantioselectivity regioselectivity catalytic reactions through optimisation ligands, counterions reaction conditions. Direct new catalysts/reactions is more difficult requires efficient exploration transition metal chemical space. A range computational descriptor generation, ranging from molecular mechanics to DFT methods, have successfully demonstrated, often conjunction with reduce cost associated TS calculations. Complex aspects reactions, such as solvent, temperature, etc., also incorporated into workflow.

Язык: Английский

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The three kingdoms—Photoinduced electron transfer cascades controlled by electronic couplings

The Journal of Chemical Physics, Год журнала: 2023, Номер 159(2)

Опубликована: Июль 10, 2023

Excited states are the key species in photocatalysis, while critical parameters that govern their applications (i) excitation energy, (ii) accessibility, and (iii) lifetime. However, molecular transition metal-based photosensitizers, there is a design tension between creation of long-lived excited (triplet), e.g., metal-to-ligand charge transfer (3MLCT) population such states. Long-lived triplet have low spin-orbit coupling (SOC) hence low. Thus, state can be populated but inefficiently. If SOC increased, efficiency improved-coming at cost decreasing A promising strategy to isolate away from metal after intersystem crossing (ISC) involves combination complex an organic donor/acceptor group. Here, we elucidate branching processes series Ru(II)-terpyridyl push-pull triads by quantum chemical simulations. Scalar-relativistic time-dependent density theory simulations reveal efficient ISC takes place along 1/3MLCT gateway Subsequently, competitive electron (ET) pathways involving chromophore, i.e., 10-methylphenothiazinyl terpyridyl ligands available. The kinetics underlying ET were investigated within semiclassical Marcus picture internal reaction coordinates connect respective photoredox intermediates. parameter governs toward chromophore either means ligand-to-ligand (3LLCT; weakly coupled) or intra-ligand (3ILCT; strongly was determined magnitude involved electronic coupling.

Язык: Английский

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Hydrogenation of CO2 to CH3OH catalyzed by a ruthenium-triphos complex: Theoretical free energy profile and microkinetic modeling

Journal of Catalysis, Год журнала: 2024, Номер 431, С. 115386 - 115386

Опубликована: Фев. 23, 2024

Язык: Английский

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Controlling hydrogen transfer dynamics in adaptive semihydrogenation of alkynes: Unveiling and directing outer- vs. inner-sphere mechanisms

Chem Catalysis, Год журнала: 2024, Номер 4(9), С. 101078 - 101078

Опубликована: Авг. 20, 2024

Язык: Английский

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Controlling the Activation at NiII‐CO22– Moieties through Lewis Acid Interactions in the Second Coordination Sphere

Chemistry - A European Journal, Год журнала: 2024, Номер unknown

Опубликована: Янв. 23, 2024

Abstract Nickel complexes with a two‐electron reduced CO 2 ligand (CO 2− , “carbonite”) are investigated regard to the influence alkali metal (AM) ions have as Lewis acids on activation of entity. For this purpose Ni II )AM (AM=Li, Na, K) moieties were accessed via deprotonation nickel‐formate compounds (AM)N( i Pr) . It was found that not only nature AM in vicinity affect activation, but also number and ligation given AM. To end effects added (AM)N(R) THF, open closed polyethers well cryptands systematically studied. In 14 cases products characterized by X‐ray diffraction correlations situation solution made. The more get detached from carbonite ligand, lower is degree aggregation. At same time extent decreased indicated structural spectroscopic analysis reactivity studies. Accompanying DFT studies showed coordinating acidic fragment withdraws small amount charge moiety, it affects internal equilibration between L tBu moieties.

Язык: Английский

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Microkinetic Molecular Volcano Plots for Enhanced Catalyst Selectivity and Activity Predictions

ACS Catalysis, Год журнала: 2024, Номер 14(13), С. 9829 - 9839

Опубликована: Июнь 17, 2024

Molecular volcano plots, which facilitate the rapid prediction of activity and selectivity prospective catalysts, have emerged as powerful tools for computational catalysis. Here, we integrate microkinetic modeling into plot framework to develop "microkinetic molecular plots". The resulting unified allows influence important reaction parameters, including temperature, time, concentration, be quickly incorporated more complex situations, such off-cycle resting states coupled catalytic cycles, tackled. Compared previous generations volcanoes, these counterparts offer a comprehensive understanding behavior, in product ratios can explicitly determined by tracking evolution each concentration over time. This is demonstrated examining two case studies, rhodium-catalyzed hydroformylation metal-catalyzed hydrosilylation, unique insights provided modeling, well ability simultaneously screen catalysts conditions, are highlighted. To construction plots/maps, introduce

Язык: Английский

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A Data‐driven Approach for Enhanced CO2 Capture with Ruthenium Complexes

Chemistry - A European Journal, Год журнала: 2024, Номер unknown

Опубликована: Июль 26, 2024

To attain carbon neutrality, significant efforts have been made to capture and utilize CO

Язык: Английский

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Diazines and Triazines as Building Blocks in Ligands for Metal-Mediated Catalytic Transformations

ACS Organic & Inorganic Au, Год журнала: 2023, Номер 4(1), С. 41 - 58

Опубликована: Окт. 23, 2023

Pyridine is a ubiquitous building block for the design of very diverse ligand platforms, many which have become indispensable catalytic transformations. Nevertheless, isosteric pyrazine, pyrimidine, and triazine congeners enjoyed thus far less privileged role in design. In this review, several applications such fragments new catalysts are presented. significant number cases described, diazine- triazine-based ligands either outperform their pyridine or offer alternative pathways enable reactivities. The potential opportunities unlocked by using these blocks discussed, origin enhanced activity highlighted where mechanistic studies available.

Язык: Английский

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A Cooperative Cobalt-Driven System for One-Carbon Extension in the Synthesis of (Z)-Silyl Enol Ethers from Aldehydes: Unlocking Regio- and Stereoselectivity

Journal of the American Chemical Society, Год журнала: 2023, Номер 145(51), С. 27922 - 27932

Опубликована: Дек. 12, 2023

The research presented herein explores a cobalt-based catalytic system, distinctively featuring cooperative boron-centric element within its intricate ligand architecture. This system is strategically engineered to enable the integration of singular carbon atom into aldehydes, process culminating in production (Z)-silyl enol ethers. Beyond offering an efficient one-pot synthesis route, this method adeptly overcomes challenges inherent conventional techniques, such as need for large amounts additives, restrictive functional group tolerance, and extreme reaction temperatures. Initial mechanistic studies suggest potential role cobalt–carbene complex catalytically significant species underscore importance borane segment. Collectively, these observations highlight advancing bond activation pursuits.

Язык: Английский

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