1
|
Liu Y, Woerpel KA. Uncatalyzed Carbometallation Involving Group 13 Elements: Carboboration and Carboalumination of Alkenes and Alkynes. SYNTHESIS-STUTTGART 2023; 55:2261-2272. [PMID: 38249784 PMCID: PMC10795483 DOI: 10.1055/s-0042-1751362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
Carbometallation of alkenes and alkynes are powerful carbon-carbon bond-forming reactions. The use of compounds containing bonds between carbon and group 13 elements, particularly boron and aluminum, are particularly attractive because of the versatility of subsequent transformations. Uncatalyzed carboboration and carboalumination represent less common classes of reactions. This Short Review discusses uncatalyzed carboboration and carboalumination reactions of alkenes and alkynes, including the reaction design and mechanism.
Collapse
Affiliation(s)
- Yudong Liu
- Department of Chemistry, New York University, 100 Washington Square East, New York, NY 10003 USA
| | - K A Woerpel
- Department of Chemistry, New York University, 100 Washington Square East, New York, NY 10003 USA
| |
Collapse
|
2
|
Tortajada A, Bole LJ, Mu M, Stanford M, Peñas-Defrutos MN, García-Melchor M, Hevia E. Sodium mediated deprotonative borylation of arenes using sterically demanding B(CH 2SiMe 3) 3: unlocking polybasic behaviour and competing lateral borane sodiation. Chem Sci 2023; 14:6538-6545. [PMID: 37350840 PMCID: PMC10283504 DOI: 10.1039/d3sc01705b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Accepted: 05/04/2023] [Indexed: 06/24/2023] Open
Abstract
The deprotonative metalation of organic molecules has become a convenient route to prepare functionalised aromatic substrates. Amongst the different metallating reagents available, sodium bases have recently emerged as a more sustainable and powerful alternative to their lithium analogues. Here we report the study of the sterically demanding electrophilic trap B(CH2SiMe3)3 for the deprotonative borylation of arenes using NaTMP (TMP = 2,2,6,6-tetramethylpiperidide) in combination with tridentate Lewis donor PMDETA (PMDETA = N,N,N',N'',N''-pentamethyldiethylenetriamine). Using anisole and benzene as model substrates, unexpected polybasic behaviour has been uncovered, which enables the formal borylation of two equivalents of the relevant arene. The combination of X-ray crystallographic and NMR monitoring studies with DFT calculations has revealed that while the first B-C bond forming process takes place via a sodiation/borylation sequence to furnish [(PMDETA)NaB(Ar)(CH2SiMe3)3] species, the second borylation step is facilitated by the formation of a borata-alkene intermediate, without the need of an external base. For non-activated benzene, it has also been found that under stoichimetric conditions the lateral sodiation of B(CH2SiMe3)3 becomes a competitive reaction pathway furnishing a novel borata-alkene complex. Showing a clear alkali-metal effect, the use of the sodium base is key to access this reactivity, while the metalation/borylation of the amine donor PMDETA is observed instead when LiTMP is used.
Collapse
Affiliation(s)
- Andreu Tortajada
- Department für Chemie und Biochemie, Universität Bern Freiestrasse 3 3012 Bern Switzerland
| | - Leonie J Bole
- Department für Chemie und Biochemie, Universität Bern Freiestrasse 3 3012 Bern Switzerland
| | - Manting Mu
- School of Chemistry, CRANN and AMBER Research Centres, Trinity College Dublin College Green Dublin 2 Ireland
| | - Martin Stanford
- Department für Chemie und Biochemie, Universität Bern Freiestrasse 3 3012 Bern Switzerland
| | - Marconi N Peñas-Defrutos
- School of Chemistry, CRANN and AMBER Research Centres, Trinity College Dublin College Green Dublin 2 Ireland
- IU CINQUIMA/Química Inorgánica, Facultad de Ciencias, Universidad de Valladolid 47071-Valladolid Spain
| | - Max García-Melchor
- School of Chemistry, CRANN and AMBER Research Centres, Trinity College Dublin College Green Dublin 2 Ireland
| | - Eva Hevia
- Department für Chemie und Biochemie, Universität Bern Freiestrasse 3 3012 Bern Switzerland
| |
Collapse
|
3
|
Zhang J, Zhang H, Qin Z, Kang Y, Hong X, Hou T. Quasiclassical Trajectory Simulation as a Protocol to Build Locally Accurate Machine Learning Potentials. J Chem Inf Model 2023; 63:1133-1142. [PMID: 36791039 DOI: 10.1021/acs.jcim.2c01497] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Direct trajectory calculations have become increasingly popular in recent computational chemistry investigations. However, the exorbitant computational cost of ab initio trajectory calculations usually limits its application in mechanistic explorations. Recently, machine learning-based potential energy surface (ML-PES) provides a powerful strategy to circumvent the heavy computational cost and meanwhile maintain the required accuracy. Despite the appealing potential, constructing a robust ML-PES is still challenging since the training set of the PES should cover a broad enough configuration space. In this work, we demonstrate that when the concerned properties could be collected by the localized sampling of the configuration space, quasiclassical trajectory (QCT) calculations can be invoked to efficiently obtain locally accurate ML-PESs. We prove our concept with two model reactions: methyl migration of i-pentane cation and dimerization of cyclopentadiene. We found that the locally accurate ML-PESs are sufficiently robust for reproducing the static and dynamic features of the reactions, including the time-resolved free energy and entropy changes, and time gaps.
Collapse
Affiliation(s)
- Jintu Zhang
- Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Haotian Zhang
- Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Zhixin Qin
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, Zhejiang, China
| | - Yu Kang
- Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, Zhejiang, China
| | - Xin Hong
- Center of Chemistry for Frontier Technologies, Department of Chemistry, State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, Zhejiang, China.,Beijing National Laboratory for Molecular Sciences, North First Street No. 2, Zhongguancun, Beijing 100190, China.,Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, School of Science, Westlake University, 18 Shilongshan Road, Hangzhou 310024, Zhejiang, China
| | - Tingjun Hou
- Innovation Institute for Artificial Intelligence in Medicine of Zhejiang University, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058, Zhejiang, China.,State Key Laboratory of Computer-aided Design & Computer Graphics, Zhejiang University, Hangzhou 310058, Zhejiang, China
| |
Collapse
|
4
|
Kee CW. Molecular Understanding and Practical In Silico Catalyst Design in Computational Organocatalysis and Phase Transfer Catalysis-Challenges and Opportunities. Molecules 2023; 28:molecules28041715. [PMID: 36838703 PMCID: PMC9966076 DOI: 10.3390/molecules28041715] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 02/03/2023] [Accepted: 02/05/2023] [Indexed: 02/25/2023] Open
Abstract
Through the lens of organocatalysis and phase transfer catalysis, we will examine the key components to calculate or predict catalysis-performance metrics, such as turnover frequency and measurement of stereoselectivity, via computational chemistry. The state-of-the-art tools available to calculate potential energy and, consequently, free energy, together with their caveats, will be discussed via examples from the literature. Through various examples from organocatalysis and phase transfer catalysis, we will highlight the challenges related to the mechanism, transition state theory, and solvation involved in translating calculated barriers to the turnover frequency or a metric of stereoselectivity. Examples in the literature that validated their theoretical models will be showcased. Lastly, the relevance and opportunity afforded by machine learning will be discussed.
Collapse
Affiliation(s)
- Choon Wee Kee
- Institute of Sustainability for Chemicals, Energy and Environment (ISCE2), Agency for Science, Technology and Research (A*STAR), 1 Pesek Road, Jurong Island, Singapore 627833, Republic of Singapore
| |
Collapse
|
5
|
Soler J, Gergel S, Klaus C, Hammer SC, Garcia-Borràs M. Enzymatic Control over Reactive Intermediates Enables Direct Oxidation of Alkenes to Carbonyls by a P450 Iron-Oxo Species. J Am Chem Soc 2022; 144:15954-15968. [PMID: 35998887 PMCID: PMC9460782 DOI: 10.1021/jacs.2c02567] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
![]()
The aerobic oxidation of alkenes to carbonyls is an important
and
challenging transformation in synthesis. Recently, a new P450-based
enzyme (aMOx) has been evolved in the laboratory to directly oxidize
styrenes to their corresponding aldehydes with high activity and selectivity.
The enzyme utilizes a heme-based, high-valent iron-oxo species as
a catalytic oxidant that normally epoxidizes alkenes, similar to other
catalysts. How the evolved aMOx enzyme suppresses the commonly preferred
epoxidation and catalyzes direct carbonyl formation is currently not
well understood. Here, we combine computational modelling together
with mechanistic experiments to study the reaction mechanism and unravel
the molecular basis behind the selectivity achieved by aMOx. Our results
describe that although both pathways are energetically accessible
diverging from a common covalent radical intermediate, intrinsic dynamic effects determine the strong preference for epoxidation.
We discovered that aMOx overrides these intrinsic preferences by controlling
the accessible conformations of the covalent radical intermediate.
This disfavors epoxidation and facilitates the formation of a carbocation
intermediate that generates the aldehyde product through a fast 1,2-hydride
migration. Electrostatic preorganization of the enzyme active site
also contributes to the stabilization of the carbocation intermediate.
Computations predicted that the hydride migration is stereoselective
due to the enzymatic conformational control over the intermediate
species. These predictions were corroborated by experiments using
deuterated styrene substrates, which proved that the hydride migration
is cis- and enantioselective. Our results demonstrate
that directed evolution tailored a highly specific active site that
imposes strong steric control over key fleeting biocatalytic intermediates,
which is essential for accessing the carbonyl forming pathway and
preventing competing epoxidation.
Collapse
Affiliation(s)
- Jordi Soler
- Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, Carrer Maria Aurèlia Capmany 69, Girona 17003, Catalonia, Spain
| | - Sebastian Gergel
- Chair of Organic Chemistry and Biocatalysis, Faculty of Chemistry, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Cindy Klaus
- Chair of Organic Chemistry and Biocatalysis, Faculty of Chemistry, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Stephan C Hammer
- Chair of Organic Chemistry and Biocatalysis, Faculty of Chemistry, Bielefeld University, Universitätsstraße 25, 33615 Bielefeld, Germany
| | - Marc Garcia-Borràs
- Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona, Carrer Maria Aurèlia Capmany 69, Girona 17003, Catalonia, Spain
| |
Collapse
|
6
|
Pandey P, Keshavamurthy S. Dynamic matching ‐ revisiting the Carpenter model. J PHYS ORG CHEM 2022. [DOI: 10.1002/poc.4404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Priyanka Pandey
- Department of Chemistry Indian Institute of Technology Kanpur Uttar Pradesh India
| | | |
Collapse
|
7
|
Chin YP, See NW, Jenkins ID, Krenske EH. Computational discoveries of reaction mechanisms: recent highlights and emerging challenges. Org Biomol Chem 2022; 20:2028-2042. [PMID: 35148363 DOI: 10.1039/d1ob02139g] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This review examines some of the notable advances and trends that have shaped the field of computational elucidation of organic reaction mechanisms over the last 10-15 years. It highlights the types of mechanistic problems that have recently become possible to study and summarizes the methodological developments that have permitted these new advances. Case studies are taken from three representative areas of organic chemistry-asymmetric catalysis, glycosylation reactions, and single electron transfer reactions-which illustrate themes common to the broader field. These include the trend towards modelling systems that are increasingly complex (both structurally and mechanistically), the growing appreciation of the mechanistic roles of non-covalent interactions, and the increasing ability to explore dynamical features of reaction mechanisms. Some interesting new challenges that have emerged in the field are identified.
Collapse
Affiliation(s)
- Yuk Ping Chin
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia.
| | - Nicholas W See
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia.
| | - Ian D Jenkins
- Griffith Institute for Drug Discovery, Griffith University, Nathan, QLD 4111, Australia
| | - Elizabeth H Krenske
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, QLD 4072, Australia.
| |
Collapse
|
8
|
Fu Y, Bernasconi L, Liu P. Ab Initio Molecular Dynamics Simulations of the S N1/S N2 Mechanistic Continuum in Glycosylation Reactions. J Am Chem Soc 2021; 143:1577-1589. [PMID: 33439656 PMCID: PMC8162065 DOI: 10.1021/jacs.0c12096] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
We report a computational approach to evaluate the reaction mechanisms of glycosylation using ab initio molecular dynamics (AIMD) simulations in explicit solvent. The reaction pathways are simulated via free energy calculations based on metadynamics and trajectory simulations using Born-Oppenheimer molecular dynamics. We applied this approach to investigate the mechanisms of the glycosylation of glucosyl α-trichloroacetimidate with three acceptors (EtOH, i-PrOH, and t-BuOH) in three solvents (ACN, DCM, and MTBE). The reactants and the solvents are treated explicitly using density functional theory. We show that the profile of the free energy surface, the synchronicity of the transition state structure, and the time gap between leaving group dissociation and nucleophile association can be used as three complementary indicators to describe the glycosylation mechanism within the SN1/SN2 continuum for a given reaction. This approach provides a reliable means to rationalize and predict reaction mechanisms and to estimate lifetimes of oxocarbenium intermediates and their dependence on the glycosyl donor, acceptor, and solvent environment.
Collapse
Affiliation(s)
- Yue Fu
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Leonardo Bernasconi
- Center for Research Computing, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
| | - Peng Liu
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, United States
- Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| |
Collapse
|
9
|
Jin S, Dang HT, Haug GC, Nguyen VD, Arman HD, Larionov OV. Deoxygenative α-alkylation and α-arylation of 1,2-dicarbonyls. Chem Sci 2020; 11:9101-9108. [PMID: 34094191 PMCID: PMC8161533 DOI: 10.1039/d0sc03118f] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 06/30/2020] [Indexed: 01/26/2023] Open
Abstract
Construction of C-C bonds at the α-carbon is a challenging but synthetically indispensable approach to α-branched carbonyl motifs that are widely represented among drugs, natural products, and synthetic intermediates. Here, we describe a simple approach to generation of boron enolates in the absence of strong bases that allows for introduction of both α-alkyl and α-aryl groups in a reaction of readily accessible 1,2-dicarbonyls and organoboranes. Obviation of unselective, strongly basic and nucleophilic reagents permits carrying out the reaction in the presence of electrophiles that intercept the intermediate boron enolates, resulting in two new α-C-C bonds in a tricomponent process.
Collapse
Affiliation(s)
- Shengfei Jin
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Hang T Dang
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Graham C Haug
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Viet D Nguyen
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Hadi D Arman
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| | - Oleg V Larionov
- Department of Chemistry, The University of Texas at San Antonio One UTSA Circle San Antonio TX 78249 USA
| |
Collapse
|
10
|
Roytman VA, Singleton DA. Solvation Dynamics and the Nature of Reaction Barriers and Ion-Pair Intermediates in Carbocation Reactions. J Am Chem Soc 2020; 142:12865-12877. [DOI: 10.1021/jacs.0c06295] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Vladislav A. Roytman
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, United States
| | - Daniel A. Singleton
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, United States
| |
Collapse
|