Convenient partial reduction of CO2 to a useful C1 building block: efficient access to 13C‐labelled N‐heterocyclic carbenes DOI Creative Commons

Nicholas A. Phillips,

Joshua S. Sapsford,

Dániel Csókás

et al.

ChemCatChem, Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 8, 2024

Abstract The selective, transition metal‐free hydrosilylation of CO 2 to CH (OSiEt 3 ) has been achieved under mild conditions and in high isolated yields (up 90%) by using Et SiH the simple, easily prepared borohydride catalyst Li + [HB(C 6 F 5 ] − . resulting ‐derived bis(silyl)acetal product—whose mechanism formation interrogated through detailed computational experimental studies—can be rapidly valorized facile synthesis N ‐heterocyclic carbenes, via their corresponding imidazolium salts. By relatively inexpensive, isotopically enriched 13 this protocol can exploited prepare NHC isotopologues that are selectively C labelled at key, ligating C2 position. This provides an electronically responsive NMR spectroscopic handle with dramatically enhanced sensitivity, which directly benefit reactivity studies both organo‐ organometallic catalysis, where use is ubiquitous.

Language: Английский

N-Heterocyclic Carbene Moiety in Highly Porous Organic Hollow Nanofibers for Efficient CO2 Conversions: A Comparative Experimental and Theoretical Study DOI
Sudip Bhattacharjee, Anjana Tripathi, Rupak Chatterjee

et al.

ACS Catalysis, Journal Year: 2024, Volume and Issue: 14(2), P. 718 - 727

Published: Jan. 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.

Language: Английский

Citations

14
Automated Transition Metal Catalysts Discovery and Optimisation with AI and Machine Learning DOI Creative Commons
S. Macé, Yingjian Xu, Bao N. Nguyen

et al.

ChemCatChem, Journal Year: 2024, Volume and Issue: 16(10)

Published: Jan. 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.

Language: Английский

Citations

9
The three kingdoms—Photoinduced electron transfer cascades controlled by electronic couplings DOI Open Access
Guangjun Yang, Georgina E. Shillito, Clara Zens

et al.

The Journal of Chemical Physics, Journal Year: 2023, Volume and Issue: 159(2)

Published: July 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.

Language: Английский

Citations

9
Controlling the Activation at NiII‐CO22– Moieties through Lewis Acid Interactions in the Second Coordination Sphere DOI Creative Commons
Siad Wolff,

Vladimir Pelmenschikov,

Robert Müller

et al.

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: unknown

Published: Jan. 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.

Language: Английский

Citations

2
Hydrogenation of CO2 to CH3OH catalyzed by a ruthenium-triphos complex: Theoretical free energy profile and microkinetic modeling DOI

Ellen V. Dalessandro,

Josefredo R. Pliego

Journal of Catalysis, Journal Year: 2024, Volume and Issue: 431, P. 115386 - 115386

Published: Feb. 23, 2024

Language: Английский

Citations

2
A Data‐driven Approach for Enhanced CO2 Capture with Ruthenium Complexes DOI
Guangchao Liang, Min Zhang

Chemistry - A European Journal, Journal Year: 2024, Volume and Issue: unknown

Published: July 26, 2024

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

Language: Английский

Citations

2
Controlling hydrogen transfer dynamics in adaptive semihydrogenation of alkynes: Unveiling and directing outer- vs. inner-sphere mechanisms DOI Creative Commons
Vishal Chugh, Jiajun Wu, Markus Leutzsch

et al.

Chem Catalysis, Journal Year: 2024, Volume and Issue: 4(9), P. 101078 - 101078

Published: Aug. 20, 2024

Language: Английский

Citations

2
Diazines and Triazines as Building Blocks in Ligands for Metal-Mediated Catalytic Transformations DOI Creative Commons

Julianna S. Doll,

Felix J. Becker,

Dragoş‐Adrian Roşca

et al.

ACS Organic & Inorganic Au, Journal Year: 2023, Volume and Issue: 4(1), P. 41 - 58

Published: Oct. 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.

Language: Английский

Citations

5
A Cooperative Cobalt-Driven System for One-Carbon Extension in the Synthesis of (Z)-Silyl Enol Ethers from Aldehydes: Unlocking Regio- and Stereoselectivity DOI Creative Commons
Soumyashree Jena,

Lars Frenzen,

Vishal Chugh

et al.

Journal of the American Chemical Society, Journal Year: 2023, Volume and Issue: 145(51), P. 27922 - 27932

Published: Dec. 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.

Language: Английский

Citations

4
Triaminoguanidine-based ionic hydrazone gels for catalyzed formylation of amines with carbon dioxide DOI
Jie Xu,

Jiawei Cui,

Di Chen

et al.

Molecular Catalysis, Journal Year: 2024, Volume and Issue: 556, P. 113908 - 113908

Published: Feb. 8, 2024

Language: Английский

Citations

1