1
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Ware SD, Zhang W, Charboneau DJ, Klein CK, Reisman SE, See KA. Electrochemical Preparation of Sm(II) Reagent Facilitated by Weakly Coordinating Anions. Chemistry 2023; 29:e202301045. [PMID: 37309269 DOI: 10.1002/chem.202301045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 06/12/2023] [Accepted: 06/12/2023] [Indexed: 06/14/2023]
Abstract
Samarium diiodide (SmI2 ) is widely used as a strong one-electron reducing agent and is often employed to form C-C bonds in complex systems. Despite their utility, SmI2 and related salts suffer from several drawbacks that render the use of Sm reducing agents in large-scale synthesis impractical. Here, we report factors influencing the electrochemical reduction of Sm(III) to Sm(II), towards the goal of electrocatalytic Sm(III) reduction. We probe the effect of supporting electrolyte, electrode material, and Sm precursor on Sm(II)/(III) redox and on the reducing power of the Sm species. We find that the coordination strength of the counteranion of the Sm salt affects the reversibility and redox potential of the Sm(II)/(III) couple and establish that the counteranion primarily determines the reducibility of Sm(III). Electrochemically generated SmI2 performs similarly to commercial SmI2 solutions in a proof-of-concept reaction. The results will provide fundamental insight to facilitate the development of Sm-electrocatalytic reactions.
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Affiliation(s)
- Skyler D Ware
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, 91125, United States
| | - Wendy Zhang
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, 91125, United States
| | - David J Charboneau
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, 91125, United States
| | - Channing K Klein
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, 91125, United States
| | - Sarah E Reisman
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, 91125, United States
| | - Kimberly A See
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, 91125, United States
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2
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Reed-Lingenfelter SN, Chen Y, Yarali M, Charboneau DJ, Curley JB, Hynek DJ, Wang M, Williams NL, Hazari N, Quek SY, Cha JJ. Compact Super Electron-Donor to Monolayer MoS 2. Nano Lett 2022; 22:4501-4508. [PMID: 35609247 DOI: 10.1021/acs.nanolett.2c01167] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The surface functionalization of two-dimensional (2D) materials with organic electron donors (OEDs) is a powerful tool to modulate the electronic properties of the material. Here we report a novel molecular dopant, Me-OED, that demonstrates record-breaking molecular doping to MoS2, achieving a carrier density of 1.10 ± 0.37 × 1014 cm-2 at optimal functionalization conditions; the achieved carrier density is much higher than those by other OEDs such as benzyl viologen and an OED based on 4,4'-bipyridine. This impressive doping power is attributed to the compact size of Me-OED, which leads to high surface coverage on MoS2. To confirm, we study tBu-OED, which has an identical reduction potential to Me-OED but is significantly larger. Using field-effect transistor measurements and spectroscopic characterization, we estimate the doping powers of Me- and tBu-OED are 0.22-0.44 and 0.11 electrons per molecule, respectively, in good agreement with calculations. Our results demonstrate that the small size of Me-OED is critical to maximizing the surface coverage and molecular interactions with MoS2, enabling us to achieve unprecedented doping of MoS2.
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Affiliation(s)
- Serrae N Reed-Lingenfelter
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06511, United States
- Energy Sciences Institute, Yale West Campus, West Haven, Connecticut 06516, United States
| | - Yifeng Chen
- Department of Physics, National University of Singapore, 117551, Singapore
| | - Milad Yarali
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06511, United States
- Energy Sciences Institute, Yale West Campus, West Haven, Connecticut 06516, United States
| | - David J Charboneau
- Department of Chemistry, Yale University, New Haven, Connecticut 06511, United States
| | - Julia B Curley
- Department of Chemistry, Yale University, New Haven, Connecticut 06511, United States
| | - David J Hynek
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06511, United States
- Energy Sciences Institute, Yale West Campus, West Haven, Connecticut 06516, United States
| | - Mengjing Wang
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06511, United States
- Energy Sciences Institute, Yale West Campus, West Haven, Connecticut 06516, United States
| | - Natalie L Williams
- Energy Sciences Institute, Yale West Campus, West Haven, Connecticut 06516, United States
- Department of Chemistry, Yale University, New Haven, Connecticut 06511, United States
| | - Nilay Hazari
- Department of Chemistry, Yale University, New Haven, Connecticut 06511, United States
| | - Su Ying Quek
- Department of Physics, National University of Singapore, 117551, Singapore
- Centre for Advanced 2D Materials, National University of Singapore, Block S14, Level 6, 6 Science Drive 2, 117546, Singapore
| | - Judy J Cha
- Department of Mechanical Engineering and Materials Science, Yale University, New Haven, Connecticut 06511, United States
- Energy Sciences Institute, Yale West Campus, West Haven, Connecticut 06516, United States
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3
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Charboneau DJ, Hazari N, Huang H, Uehling MR, Zultanski SL. Homogeneous Organic Electron Donors in Nickel-Catalyzed Reductive Transformations. J Org Chem 2022; 87:7589-7609. [PMID: 35671350 DOI: 10.1021/acs.joc.2c00462] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Many contemporary organic transformations, such as Ni-catalyzed cross-electrophile coupling (XEC), require a reductant. Typically, heterogeneous reductants, such as Zn0 or Mn0, are used as the electron source in these reactions. Although heterogeneous reductants are highly practical for preparative-scale batch reactions, they can lead to complications in performing reactions on process scale and are not easily compatible with modern applications, such as flow chemistry. In principle, homogeneous organic reductants can address some of the challenges associated with heterogeneous reductants and also provide greater control of the reductant strength, which can lead to new reactivity. Nevertheless, homogeneous organic reductants have rarely been used in XEC. In this Perspective, we summarize recent progress in the use of homogeneous organic electron donors in Ni-catalyzed XEC and related reactions, discuss potential synthetic and mechanistic benefits, describe the limitations that inhibit their implementation, and outline challenges that need to be solved in order for homogeneous organic reductants to be widely utilized in synthetic chemistry. Although our focus is on XEC, our discussion of the strengths and weaknesses of different methods for introducing electrons is general to other reductive transformations.
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Affiliation(s)
- David J Charboneau
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Nilay Hazari
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Haotian Huang
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Mycah R Uehling
- Discovery Chemistry, HTE and Lead Discovery Capabilities, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Susan L Zultanski
- Department of Process Research and Development, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
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4
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Deziel AP, Espinosa MR, Pavlovic L, Charboneau DJ, Hazari N, Hopmann KH, Mercado BQ. Ligand and solvent effects on CO2 insertion into group 10 metal alkyl bonds. Chem Sci 2022; 13:2391-2404. [PMID: 35342547 PMCID: PMC8867079 DOI: 10.1039/d1sc06346d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Accepted: 01/31/2022] [Indexed: 11/29/2022] Open
Abstract
The insertion of carbon dioxide into metal element σ-bonds is an important elementary step in many catalytic reactions for carbon dioxide valorization. Here, the insertion of carbon dioxide into a family of group 10 alkyl complexes of the type (RPBP)M(CH3) (RPBP = B(NCH2PR2)2C6H4−; R = Cy or tBu; M = Ni or Pd) to generate κ1-acetate complexes of the form (RPBP)M{OC(O)CH3} is investigated. This involved the preparation and characterization of a number of new complexes supported by the unusual RPBP ligand, which features a central boryl donor that exerts a strong trans-influence, and the identification of a new decomposition pathway that results in C–B bond formation. In contrast to other group 10 methyl complexes supported by pincer ligands, carbon dioxide insertion into (RPBP)M(CH3) is facile and occurs at room temperature because of the high trans-influence of the boryl donor. Given the mild conditions for carbon dioxide insertion, we perform a rare kinetic study on carbon dioxide insertion into a late-transition metal alkyl species using (tBuPBP)Pd(CH3). These studies demonstrate that the Dimroth–Reichardt parameter for a solvent correlates with the rate of carbon dioxide insertion and that Lewis acids do not promote insertion. DFT calculations indicate that insertion into (tBuPBP)M(CH3) (M = Ni or Pd) proceeds via an SE2 mechanism and we compare the reaction pathway for carbon dioxide insertion into group 10 methyl complexes with insertion into group 10 hydrides. Overall, this work provides fundamental insight that will be valuable for the development of improved and new catalysts for carbon dioxide utilization. The kinetics of carbon dioxide insertion into a pincer-supported palladium methyl complex are studied. The complex inserts carbon dioxide at room temperature, and we explore both solvent and Lewis acid effects on carbon dioxide insertion.![]()
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Affiliation(s)
- Anthony P. Deziel
- Department of Chemistry, Yale University, P. O. Box 208107, New Haven, Connecticut, 06520, USA
| | - Matthew R. Espinosa
- Department of Chemistry, Yale University, P. O. Box 208107, New Haven, Connecticut, 06520, USA
| | - Ljiljana Pavlovic
- Department of Chemistry, UiT The Arctic University of Norway, N-9307 Tromsø, Norway
| | - David J. Charboneau
- Department of Chemistry, Yale University, P. O. Box 208107, New Haven, Connecticut, 06520, USA
| | - Nilay Hazari
- Department of Chemistry, Yale University, P. O. Box 208107, New Haven, Connecticut, 06520, USA
| | - Kathrin H. Hopmann
- Department of Chemistry, UiT The Arctic University of Norway, N-9307 Tromsø, Norway
| | - Brandon Q. Mercado
- Department of Chemistry, Yale University, P. O. Box 208107, New Haven, Connecticut, 06520, USA
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5
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Charboneau DJ, Huang H, Barth EL, Germe CC, Hazari N, Mercado BQ, Uehling MR, Zultanski SL. Tunable and Practical Homogeneous Organic Reductants for Cross-Electrophile Coupling. J Am Chem Soc 2021; 143:21024-21036. [PMID: 34846142 DOI: 10.1021/jacs.1c10932] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The syntheses of four new tunable homogeneous organic reductants based on a tetraaminoethylene scaffold are reported. The new reductants have enhanced air stability compared to current homogeneous reductants for metal-mediated reductive transformations, such as cross-electrophile coupling (XEC), and are solids at room temperature. In particular, the weakest reductant is indefinitely stable in air and has a reduction potential of -0.85 V versus ferrocene, which is significantly milder than conventional reductants used in XEC. All of the new reductants can facilitate C(sp2)-C(sp3) Ni-catalyzed XEC reactions and are compatible with complex substrates that are relevant to medicinal chemistry. The reductants span a range of nearly 0.5 V in reduction potential, which allows for control over the rate of electron transfer events in XEC. Specifically, we report a new strategy for controlled alkyl radical generation in Ni-catalyzed C(sp2)-C(sp3) XEC. The key to our approach is to tune the rate of alkyl radical generation from Katritzky salts, which liberate alkyl radicals upon single electron reduction, by varying the redox potentials of the reductant and Katritzky salt utilized in catalysis. Using our method, we perform XEC reactions between benzylic Katritzky salts and aryl halides. The method tolerates a variety of functional groups, some of which are particularly challenging for most XEC transformations. Overall, we expect that our new reductants will both replace conventional homogeneous reductants in current reductive transformations due to their stability and relatively facile synthesis and lead to the development of novel synthetic methods due to their tunability.
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Affiliation(s)
- David J Charboneau
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Haotian Huang
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Emily L Barth
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Cameron C Germe
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Nilay Hazari
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Brandon Q Mercado
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Mycah R Uehling
- Discovery Chemistry, HTE and Lead Discovery Capabilities, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
| | - Susan L Zultanski
- Department of Process Research and Development, Merck & Co., Inc., Kenilworth, New Jersey 07033, United States
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6
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Edington SC, Perez EH, Charboneau DJ, Menges FS, Hazari N, Johnson MA. Chemical Reduction of Ni II Cyclam and Characterization of Isolated Ni I Cyclam with Cryogenic Vibrational Spectroscopy and Inert-Gas-Mediated High-Resolution Mass Spectrometry. J Phys Chem A 2021; 125:6715-6721. [PMID: 34324319 DOI: 10.1021/acs.jpca.1c05016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
NiII cyclam (cyclam = 1,4,8,11-tetraazacyclotetradecane) is an efficient catalyst for the selective reduction of CO2 to CO. A crucial elementary step in the proposed catalytic cycle is the coordination of CO2 to a NiI cyclam intermediate. Isolation and spectroscopic characterization of this labile NiI species without solvent has proven to be challenging, however, and only partial IR spectra have previously been reported using multiple photon fragmentation of ions generated by gas-phase electron transfer to the NiII cyclam dication at 300 K. Here, we report a chemical reduction method that efficiently prepares NiI cyclam in solution. This enables the NiI complex to be transferred into a cryogenic photofragmentation mass spectrometer using inert-gas-mediated electrospray ionization. The vibrational spectra of the 30 K ion using both H2 and N2 messenger tagging over the range 800-4000 cm-1 were then measured. The resulting spectra were analyzed with the aid of electronic structure calculations, which show strong method dependence in predicted band positions and small molecule activation. The conformational changes of the cyclam ligand induced by binding of the open shell NiI cation were compared with those caused by the spherical, closed-shell LiI cation, which has a similar ionic radius. We also report the vibrational spectrum of a NiI cyclam complex with a strongly bound O2 ligand. The cyclam ligand supporting this species exhibits a large conformational change compared to the complexes with weakly bound N2 and H2, which is likely due to significant charge transfer from Ni to the coordinated O2.
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Affiliation(s)
- Sean C Edington
- Sterling Chemistry Laboratory, Chemistry Department, Yale University, New Haven, Connecticut 06520, United States
| | - Evan H Perez
- Sterling Chemistry Laboratory, Chemistry Department, Yale University, New Haven, Connecticut 06520, United States
| | - David J Charboneau
- Sterling Chemistry Laboratory, Chemistry Department, Yale University, New Haven, Connecticut 06520, United States
| | - Fabian S Menges
- Sterling Chemistry Laboratory, Chemistry Department, Yale University, New Haven, Connecticut 06520, United States
| | - Nilay Hazari
- Sterling Chemistry Laboratory, Chemistry Department, Yale University, New Haven, Connecticut 06520, United States
| | - Mark A Johnson
- Sterling Chemistry Laboratory, Chemistry Department, Yale University, New Haven, Connecticut 06520, United States
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7
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Charboneau DJ, Barth EL, Hazari N, Uehling MR, Zultanski SL. A Widely Applicable Dual Catalytic System for Cross-Electrophile Coupling Enabled by Mechanistic Studies. ACS Catal 2020; 10:12642-12656. [PMID: 33628617 DOI: 10.1021/acscatal.0c03237] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A dual catalytic system for cross-electrophile coupling reactions between aryl halides and alkyl halides that features a Ni catalyst, a Co cocatalyst, and a mild homogeneous reductant is described. Mechanistic studies indicate that the Ni catalyst activates the aryl halide, while the Co cocatalyst activates the alkyl halide. This allows the system to be rationally optimized for a variety of substrate classes by simply modifying the loadings of the Ni and Co catalysts based on the reaction product profile. For example, the coupling of aryl bromides and aryl iodides with alkyl bromides, alkyl iodides, and benzyl chlorides is demonstrated using the same Ni and Co catalysts under similar reaction conditions but with different optimal catalyst loadings in each case. Our system is tolerant of numerous functional groups and is capable of coupling heteroaryl halides, di-ortho-substituted aryl halides, pharmaceutically relevant druglike aryl halides, and a diverse range of alkyl halides. Additionally, the dual catalytic platform facilitates a series of selective one-pot three-component cross-electrophile coupling reactions of bromo(iodo)arenes with two distinct alkyl halides. This demonstrates the unique level of control that the platform provides and enables the rapid generation of molecular complexity. The system can be readily utilized for a wide range of applications as all reaction components are commercially available, the reaction is scalable, and toxic amide-based solvents are not required. It is anticipated that this strategy, as well as the underlying mechanistic framework, will be generalizable to other cross-electrophile coupling reactions.
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Affiliation(s)
- David J. Charboneau
- Department of Chemistry, Yale University, P. O. Box 208107, New Haven, Connecticut 06520, United States
| | - Emily L. Barth
- Department of Chemistry, Yale University, P. O. Box 208107, New Haven, Connecticut 06520, United States
| | - Nilay Hazari
- Department of Chemistry, Yale University, P. O. Box 208107, New Haven, Connecticut 06520, United States
| | - Mycah R. Uehling
- Merck & Co., Inc., Discovery Chemistry, HTE and Lead Discovery Capabilities, Kenilworth, New Jersey 07033, United States
| | - Susan L. Zultanski
- Merck & Co., Inc., Department of Process Research and Development, Rahway, New Jersey 07065, United States
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8
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Charboneau DJ, Brudvig GW, Hazari N, Lant HMC, Saydjari AK. Development of an Improved System for the Carboxylation of Aryl Halides through Mechanistic Studies. ACS Catal 2019; 9:3228-3241. [PMID: 31007967 DOI: 10.1021/acscatal.9b00566] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The nickel-catalyzed carboxylation of organic halides or pseudohalides using carbon dioxide is an emerging method to prepare synthetically valuable carboxylic acids. Here, we report a detailed mechanistic investigation of these reactions using the carboxylation of aryl halides with (PPh3)2NiIICl2 as a model reaction. Our studies allow us to understand several general features of nickel-catalyzed carboxylation reactions. For example, we demonstrate that both a Lewis acid and halide source are beneficial for catalysis. To this end, we establish that heterogeneous Mn(0) and Zn(0) reductants are multifaceted reagents that generate noninnocent Mn(II) or Zn(II) Lewis acids upon oxidation. In a key result, a rare example of a well-defined nickel(I) aryl complex is isolated, and it is demonstrated that its reaction with carbon dioxide results in the formation of a carboxylic acid in high yield (after workup). The carbon dioxide insertion product undergoes rapid decomposition, which ca These three oxidation states correspond to the onbe circumvented by a ligand metathesis reaction with a halide source. Our studies have led to both a revised mechanism and the development of a broadly applicable strategy to improve reductive carboxylation reactions. A critical component of this strategy is that we have replaced the heterogeneous Mn(0) reductant typically used in catalysis with a well-defined homogeneous organic reductant. Through its use, we have increased the range of ancillary ligands, additives, and substrates that are compatible with the reaction. This has enabled us to perform reductive carboxylations at low catalyst loadings. Additionally, we demonstrate that reductive carboxylations of organic (pseudo)halides can be achieved in high yields in more practically useful, non-amide solvents. Our results describe a mechanistically guided strategy to improve reductive carboxylations through the use of a homogeneous organic reductant, which may be broadly translatable to a wide range of cross-electrophile coupling reactions.
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Affiliation(s)
- David J. Charboneau
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Gary W. Brudvig
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Nilay Hazari
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Hannah M. C. Lant
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Andrew K. Saydjari
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
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9
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Espinosa MR, Charboneau DJ, Garcia de Oliveira A, Hazari N. Controlling Selectivity in the Hydroboration of Carbon Dioxide to the Formic Acid, Formaldehyde, and Methanol Oxidation Levels. ACS Catal 2018. [DOI: 10.1021/acscatal.8b03894] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Matthew R. Espinosa
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - David J. Charboneau
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - André Garcia de Oliveira
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Nilay Hazari
- Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
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10
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Beromi MM, Banerjee G, Brudvig GW, Charboneau DJ, Hazari N, Lant HMC, Mercado BQ. Modifications to the Aryl Group of dppf-Ligated Ni σ‑Aryl Precatalysts: Impact on Speciation and Catalytic Activity in Suzuki-Miyaura Coupling Reactions. Organometallics 2018; 37:3943-3955. [PMID: 31736532 DOI: 10.1021/acs.organomet.8b00589] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
There is currently significant interest in the development of efficient nickel precatalysts for cross-coupling. In this work, 14 nickel(II) precatalysts of the form (dppf)Ni(aryl)(X) (dppf = 1,1'-bis(diphenylphosphino)-ferrocene, X = Cl, Br) were synthesized. In particular, both the electronic and steric properties of the aryl group were modified to understand how this affects precatalyst activation. Using EPR spectroscopy, it was demonstrated that the amount of off-cycle nickel(I) species which are formed via comproportionation during precatalyst activation varies depending on the nature of the aryl group. For example, sterically bulky aryl groups reduce comproportionation. Additionally, the catalytic activity of the family of precatalysts was evaluated in five different Suzuki-Miyaura coupling reactions. The results from these catalytic studies provide information about how precatalyst structure affects catalytic efficiency, which may be useful for the rational design of improved nickel precatalysts for cross-coupling.
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Affiliation(s)
- Megan Mohadjer Beromi
- The Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Gourab Banerjee
- The Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Gary W Brudvig
- The Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - David J Charboneau
- The Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Nilay Hazari
- The Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Hannah M C Lant
- The Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Brandon Q Mercado
- The Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
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11
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Qu F, Park S, Martinez K, Gray JL, Thowfeik FS, Lundeen JA, Kuhn AE, Charboneau DJ, Gerlach DL, Lockart MM, Law JA, Jernigan KL, Chambers N, Zeller M, Piro NA, Kassel WS, Schmehl RH, Paul JJ, Merino EJ, Kim Y, Papish ET. Ruthenium Complexes are pH-Activated Metallo Prodrugs (pHAMPs) with Light-Triggered Selective Toxicity Toward Cancer Cells. Inorg Chem 2017. [DOI: 10.1021/acs.inorgchem.7b01065] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Affiliation(s)
- Fengrui Qu
- Department
of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487-0336, United States
| | - Seungjo Park
- Department
of Chemical and Biological Engineering, The University of Alabama, Tuscaloosa, Alabama 35487-0203, United States
| | - Kristina Martinez
- Department
of Chemistry, Tulane University, New Orleans, Louisiana 70118, United States
| | - Jessica L. Gray
- Department
of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487-0336, United States
| | | | - John A. Lundeen
- Department
of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487-0336, United States
| | - Ashley E. Kuhn
- Department
of Chemistry, Villanova University, Villanova, Pennsylvania 19085, United States
| | - David J. Charboneau
- Department
of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487-0336, United States
- Department
of Chemistry, Villanova University, Villanova, Pennsylvania 19085, United States
| | - Deidra L. Gerlach
- Department
of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487-0336, United States
| | - Molly M. Lockart
- Department
of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487-0336, United States
| | - James A. Law
- Department
of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487-0336, United States
| | - Katherine L. Jernigan
- Department
of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487-0336, United States
| | - Nicole Chambers
- Department
of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487-0336, United States
| | - Matthias Zeller
- Department
of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Nicholas A. Piro
- Department
of Chemistry, Albright College, Reading, Pennsylvania 19612, United States
| | - W. Scott Kassel
- Department
of Chemistry, Villanova University, Villanova, Pennsylvania 19085, United States
| | - Russell H. Schmehl
- Department
of Chemistry, Tulane University, New Orleans, Louisiana 70118, United States
| | - Jared J. Paul
- Department
of Chemistry, Villanova University, Villanova, Pennsylvania 19085, United States
| | - Edward J. Merino
- Department
of Chemistry, University of Cincinnati, Cincinnati, Ohio 45221, United States
| | - Yonghyun Kim
- Department
of Chemical and Biological Engineering, The University of Alabama, Tuscaloosa, Alabama 35487-0203, United States
| | - Elizabeth T. Papish
- Department
of Chemistry, The University of Alabama, Tuscaloosa, Alabama 35487-0336, United States
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Charboneau DJ, Balcells D, Hazari N, Lant HMC, Mayer JM, Melvin PR, Mercado BQ, Morris WD, Repisky M, Suh HW. Dinitrogen-Facilitated Reversible Formation of a Si–H Bond in a Pincer-Supported Ni Complex. Organometallics 2016. [DOI: 10.1021/acs.organomet.6b00514] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
- David J. Charboneau
- The
Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - David Balcells
- Centre
for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O.
Box 1033, Blindern, N-0315 Oslo, Norway
| | - Nilay Hazari
- The
Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Hannah M. C. Lant
- The
Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - James M. Mayer
- The
Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Patrick R. Melvin
- The
Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Brandon Q. Mercado
- The
Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Wesley D. Morris
- The
Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
| | - Michal Repisky
- Centre
for Theoretical and Computational Chemistry (CTCC), University of Tromsø-The Arctic University of Norway, N-9037 Tromsø, Norway
| | - Hee-Won Suh
- The
Department of Chemistry, Yale University, P.O. Box 208107, New Haven, Connecticut 06520, United States
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Charboneau DJ, Piro NA, Kassel WS, Dudley TJ, Paul JJ. Reprint of: Structural, electronic and acid/base properties of [Ru(bpy)(bpy(OH)2)2]2+ (bpy = 2,2′-bipyridine, bpy(OH)2= 4,4′-dihydroxy-2,2′-bipyridine). Polyhedron 2016. [DOI: 10.1016/j.poly.2016.05.042] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Charboneau DJ, Piro NA, Kassel WS, Dudley TJ, Paul JJ. Structural, electronic and acid/base properties of [Ru(bpy)(bpy(OH)2)2]2+ (bpy=2,2′-bipyridine, bpy(OH)2=4,4′-dihydroxy-2,2′-bipyridine). Polyhedron 2015. [DOI: 10.1016/j.poly.2015.02.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Marelius DC, Bhagan S, Charboneau DJ, Schroeder KM, Kamdar JM, McGettigan AR, Freeman BJ, Moore CE, Rheingold AL, Cooksy AL, Smith DK, Paul JJ, Papish ET, Grotjahn DB. How Do Proximal Hydroxy or Methoxy Groups on the Bidentate Ligand Affect [(2,2′;6′,2"-Terpyridine)Ru(N,N)X] Water-Oxidation Catalysts? Synthesis, Characterization, and Reactivity at Acidic and Near-Neutral pH. Eur J Inorg Chem 2013. [DOI: 10.1002/ejic.201300826] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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Hufziger KT, Thowfeik FS, Charboneau DJ, Nieto I, Dougherty WG, Kassel WS, Dudley TJ, Merino EJ, Papish ET, Paul JJ. Ruthenium dihydroxybipyridine complexes are tumor activated prodrugs due to low pH and blue light induced ligand release. J Inorg Biochem 2013; 130:103-11. [PMID: 24184694 DOI: 10.1016/j.jinorgbio.2013.10.008] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2013] [Revised: 10/08/2013] [Accepted: 10/08/2013] [Indexed: 01/07/2023]
Abstract
Ruthenium drugs are potent anti-cancer agents, but inducing drug selectivity and enhancing their modest activity remain challenging. Slow Ru ligand loss limits the formation of free sites and subsequent binding to DNA base pairs. Herein, we designed a ligand that rapidly dissociates upon irradiation at low pH. Activation at low pH can lead to cancer selectivity, since many cancer cells have higher metabolism (and thus lower pH) than non-cancerous cells. We have used the pH sensitive ligand, 6,6'-dihydroxy-2,2'-bipyridine (66'bpy(OH)2), to generate [Ru(bpy)2(66'(bpy(OH)2)](2+), which contains two acidic hydroxyl groups with pKa1=5.26 and pKa2=7.27. Irradiation when protonated leads to photo-dissociation of the 66'bpy(OH)2 ligand. An in-depth study of the structural and electronic properties of the complex was carried out using X-ray crystallography, electrochemistry, UV/visible spectroscopy, and computational techniques. Notably, RuN bond lengths in the 66'bpy(OH)2 complex are longer (by ~0.3Å) than in polypyridyl complexes that lack 6 and 6' substitution. Thus, the longer bond length predisposes the complex for photo-dissociation and leads to the anti-cancer activity. When the complex is deprotonated, the 66'bpy(O(-))2 ligand molecular orbitals mix heavily with the ruthenium orbitals, making new mixed metal-ligand orbitals that lead to a higher bond order. We investigated the anti-cancer activities of [Ru(bpy)2(66'(bpy(OH)2)](2+), [Ru(bpy)2(44'(bpy(OH)2)](2+), and [Ru(bpy)3](2+) (44'(bpy(OH)2=4,4'-dihydroxy-2,2'-bipyridine) in HeLa cells, which have a relatively low pH. It is found that [Ru(bpy)2(66'(bpy(OH)2)](2+) is more cytotoxic than the other ruthenium complexes studied. Thus, we have identified a pH sensitive ruthenium scaffold that can be exploited for photo-induced anti-cancer activity.
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Affiliation(s)
- Kyle T Hufziger
- Department of Chemistry, Villanova University, 800 Lancaster Ave., Villanova, PA 19085, United States
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