1
|
Xie KA, Bednarova E, Joe CL, Lin C, Sherwood TC, Simmons EM, Lainhart BC, Rovis T. Orange Light-Driven C(sp 2)-C(sp 3) Cross-Coupling via Spin-Forbidden Ir(III) Metallaphotoredox Catalysis. J Am Chem Soc 2023; 145:19925-19931. [PMID: 37642382 DOI: 10.1021/jacs.3c06285] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
We report the development and characterization of a library of Ir(III) photocatalysts capable of undergoing spin-forbidden excitation (SFE) under orange light irradiation (595 nm). These catalysts were successfully applied to the construction of synthetically valuable C(sp2)-C(sp3) bonds inaccessible with existing methods of low-energy light-driven dual nickel/photoredox catalysis, demonstrating the synthetic utility of this photocatalyst family. The photocatalysts are capable of accessing both oxidatively and reductively activated coupling partners, illustrated through deaminative arylation and potassium alkyl trifluoroborate cross-coupling reactions with aryl halides. We demonstrate diverse substrate scopes of both cross-coupling paradigms under mild conditions in the first example of low-energy light-driven C(sp2)-C(sp3) metallaphotoredox coupling.
Collapse
Affiliation(s)
- Katherine A Xie
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Eva Bednarova
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| | - Candice L Joe
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Chenxi Lin
- Department of Chemistry, Barnard College, New York, New York 10027, United States
| | - Trevor C Sherwood
- Small Molecule Drug Discovery, Bristol Myers Squibb, Princeton, New Jersey 08543, United States
| | - Eric M Simmons
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Brendan C Lainhart
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Tomislav Rovis
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| |
Collapse
|
2
|
Rovis T, Beck LR, Xie KA, Goldschmid SL, Kariofillis SK, Joe CL, Sherwood TC, Sezen-Edmonds M. Red-Shifting Blue Light Photoredox Catalysis for Organic Synthesis: A Graphical Review. SynOpen 2023. [DOI: 10.1055/s-0040-1720060] [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: 03/06/2023] Open
Abstract
AbstractPhotoredox catalysis has revolutionized synthetic chemistry in recent decades. However, the field has traditionally used high-energy blue/ultraviolet light to activate chromophores. High-energy irradiation is associated with several drawbacks (e.g., activation of sensitive functional groups, undesired metal-ligand homolysis, background activation of molecules, and poor penetration), which has led researchers to develop alternative systems with lower energy deep red (DR) or near-infrared (NIR) light. This graphical review provides a concise overview of photophysical principles relevant to photoredox catalysis. Several applications that benefit from low-energy irradiation, such as large-scale batch reactions, photodynamic therapy, biological labeling, and multi-photon excitation are reviewed.
Collapse
|
3
|
Bi C, Chadwick J, Davies ML, DelMonte AJ, Geng P, Glace AW, Green RA, Gurak JA, Haley MW, He BL, Inankur B, Jamison CR, Joe CL, Kolotuchin S, Lin D, Lou S, Nye J, Ortiz A, Purdum GE, Rosso VW, Shah M, Simmons EM, Stevens JM, Strotman NA, Tan Y, Zhang L. Coupling-Condensation Strategy for the Convergent Synthesis of an Imidazole-Fused 2-Aminoquinoline NLRP3 Agonist. J Org Chem 2023; 88:384-394. [PMID: 36516991 DOI: 10.1021/acs.joc.2c02395] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The development of a convergent route to the NLRP3 (nucleotide-binding domain and leucine-rich repeat-containing protein 3) agonist BMS-986299 is reported. The synthesis relies on a key Miyaura borylation and a tandem Suzuki-Miyaura coupling between an iodoimidazole and an o-aminochloroarene, followed by acid-mediated cyclization to afford the aminoquinoline core. The subsequent Boc cleavage and regioselective acylation afford the target compound. Two routes to the iodoimidazole intermediate are presented, along with the synthesis of the o-aminochloroarene via Negishi coupling. The convergent six-step route leads to an 80% reduction in process mass intensity compared to the linear enabling synthesis.
Collapse
Affiliation(s)
- Cong Bi
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - James Chadwick
- Chemical Process Development, Bristol Myers Squibb, Reeds Lane, Moreton, Wirral CH46 1QW, U.K
| | - Merrill L Davies
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Albert J DelMonte
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Peng Geng
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Andrew W Glace
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Rebecca A Green
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - John A Gurak
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Matthew W Haley
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Brian L He
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Bahar Inankur
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Christopher R Jamison
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Candice L Joe
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Sergei Kolotuchin
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Dong Lin
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Sha Lou
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Jeffrey Nye
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Adrian Ortiz
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Geoffrey E Purdum
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Victor W Rosso
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Mansi Shah
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Eric M Simmons
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Jason M Stevens
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Neil A Strotman
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Yichen Tan
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Ling Zhang
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| |
Collapse
|
4
|
Goldschmid SL, Soon Tay NE, Joe CL, Lainhart BC, Sherwood TC, Simmons EM, Sezen-Edmonds M, Rovis T. Overcoming Photochemical Limitations in Metallaphotoredox Catalysis: Red-Light-Driven C-N Cross-Coupling. J Am Chem Soc 2022; 144:22409-22415. [PMID: 36417474 DOI: 10.1021/jacs.2c09745] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Aryl amination is an essential transformation for medicinal, process, and materials chemistry. In addition to classic Buchwald-Hartwig amination conditions, blue-light-driven metallaphotoredox catalysis has emerged as a valuable tool for C-N cross-coupling. However, blue light suffers from low penetration through reaction media, limiting its scalability for industrial purposes. In addition, blue light enhances unwanted side-product formation in metallaphotoredox catalysis, namely hydrodehalogenation. Low-energy light, such as deep red (DR) or near-infrared (NIR), offers a solution to this problem as it can provide enhanced penetration through reaction media as compared to higher-energy wavelengths. Herein, we show that low-energy light can also enhance the desired reactivity in metallaphotoredox catalysis by suppressing unwanted hydrodehalogenation. We hypothesize that the reduced side product is formed by direct photolysis of the aryl-nickel bond by the high-energy light, leading to the generation of aryl radicals. Using deep-red or near-infrared light and an osmium photocatalyst, we demonstrate an enhanced scope of (hetero)aryl bromides and amine-based nucleophiles with minimal formation of hydrodehalogenation byproducts.
Collapse
Affiliation(s)
- Samantha L Goldschmid
- Department of Chemistry, Columbia University, New York, New York10027, United States
| | - Nicholas Eng Soon Tay
- Department of Chemistry, Columbia University, New York, New York10027, United States
| | - Candice L Joe
- Chemical Process Development, Bristol Myers Squibb, New Brunswick, New Jersey08903, United States
| | - Brendan C Lainhart
- Chemical Process Development, Bristol Myers Squibb, New Brunswick, New Jersey08903, United States
| | - Trevor C Sherwood
- Small Molecule Drug Discovery, Bristol Myers Squibb, Princeton, New Jersey08543, United States
| | - Eric M Simmons
- Chemical Process Development, Bristol Myers Squibb, New Brunswick, New Jersey08903, United States
| | - Melda Sezen-Edmonds
- Chemical Process Development, Bristol Myers Squibb, New Brunswick, New Jersey08903, United States
| | - Tomislav Rovis
- Department of Chemistry, Columbia University, New York, New York10027, United States
| |
Collapse
|
5
|
Hao W, Joe CL, Darù A, Ayers S, Ramirez A, Sandhu B, Daley RA, Chen JS, Schmidt MA, Blackmond DG. Kinetic and Thermodynamic Considerations in the Rh-Catalyzed Enantioselective Hydrogenation of 2-Pyridyl-Substituted Alkenes. ACS Catal 2022; 12:5961-5969. [PMID: 37727697 PMCID: PMC10508913 DOI: 10.1021/acscatal.2c00231] [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] [Indexed: 11/30/2022]
Abstract
The mechanism of asymmetric hydrogenation of 2-pyridyl alkenes catalyzed by chiral Rh-phosphine complexes at ambient temperature is examined using kinetic, spectroscopic, and computational tools. The reaction proceeds with reversible substrate binding followed by rate-determining addition of hydrogen. Substrate binding occurs only through the pyridine nitrogen in contrast to other substrate classes exhibiting stronger substrate direction. The lack of influence of hydrogen pressure on the product enantiomeric excess suggests that a pre-equilibrium in substrate binding is maintained across the pressure range investigated. An off-cycle Rh-hydride species is implicated in the mild catalyst deactivation observed. In contrast to Ru-phosphine-catalyzed reactions of the same substrate class, the stereochemical outcome in this system correlates generally with the relative stability of the E and Z rotamers of the substrate.
Collapse
Affiliation(s)
- Wei Hao
- Department of Chemistry, Scripps Research, La Jolla, California 92037, United States
| | - Candice L Joe
- Chemical Process Development, Bristol Myers Squibb Co., New Brunswick, New Jersey 08903, United States
| | - Andrea Darù
- Department of Chemistry, Scripps Research, La Jolla, California 92037, United States
| | - Sloan Ayers
- Chemical Process Development, Bristol Myers Squibb Co., New Brunswick, New Jersey 08903, United States
| | - Antonio Ramirez
- Chemical Process Development, Bristol Myers Squibb Co., New Brunswick, New Jersey 08903, United States
| | - Bhupinder Sandhu
- Chemical Process Development, Bristol Myers Squibb Co., New Brunswick, New Jersey 08903, United States
| | - Ryan A Daley
- Department of Chemistry, Scripps Research, La Jolla, California 92037, United States
| | - Jason S Chen
- Department of Chemistry and Automated Synthesis Facility, Scripps Research, La Jolla, California 92037, United States
| | - Michael A Schmidt
- Chemical Process Development, Bristol Myers Squibb Co., New Brunswick, New Jersey 08903, United States
| | - Donna G Blackmond
- Department of Chemistry, Scripps Research, La Jolla, California 92037, United States
| |
Collapse
|
6
|
Gallagher WP, Coombs JR, Guerrero CA, Mudryk BM, Katipally K, Joe CL, Rupasinghe S, Zhu J, González-Bobes F. Asymmetric Synthesis of the Cyclohexyl Fragment in RORγt Inhibitor (BMS-986251) Enabled by a Dynamic Kinetic Resolution of Hageman’s Ester. Org Process Res Dev 2022. [DOI: 10.1021/acs.oprd.1c00339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- William P. Gallagher
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - John R. Coombs
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Carlos A. Guerrero
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Boguslaw M. Mudryk
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Kishta Katipally
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Candice L. Joe
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Sanjeewa Rupasinghe
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Jason Zhu
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Francisco González-Bobes
- Chemical Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| |
Collapse
|
7
|
Hao W, Joe CL, Ayers S, Darù A, Daley RA, Chen JS, Domanski M, Schmidt MA, Blackmond DG. Ru-Catalyzed Enantioselective Hydrogenation of 2-Pyridyl-Substituted Alkenes and Substrate-Mediated H/D Exchange. ACS Catal 2022; 12:1150-1160. [PMID: 36386561 PMCID: PMC9648516 DOI: 10.1021/acscatal.1c05061] [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: 01/23/2023]
Abstract
A highly efficient and enantioselective asymmetric hydrogenation catalyzed by Ru-DTBM-segphos is reported for a broad range of pyridine-pyrroline tri-substituted alkenes. Kinetic, spectroscopic, and computational studies suggest that addition of H2 is rate-determining and that alkene insertion is the enantio-determining step. These studies also reveal an intriguing Ru-catalyzed H/D exchange process that is facilitated by the substrate at room temperature and low pressure where hydrogenation activity is suppressed. These studies lead to a mechanistic proposal that further defines the roles of hydrogen gas, Ru-H species, and protic solvents in this catalytic system.
Collapse
Affiliation(s)
- Wei Hao
- Department of Chemistry, Scripps Research, La Jolla, CA 92037 USA
| | - Candice L. Joe
- Chemical Development, Bristol Myers Squibb Corp., New Brunswick, NJ 08903 USA
| | - Sloan Ayers
- Chemical Development, Bristol Myers Squibb Corp., New Brunswick, NJ 08903 USA
| | - Andrea Darù
- Department of Chemistry, Scripps Research, La Jolla, CA 92037 USA
| | - Ryan A. Daley
- Department of Chemistry, Scripps Research, La Jolla, CA 92037 USA
| | - Jason S. Chen
- Department of Chemistry, Scripps Research, La Jolla, CA 92037 USA,Automated Synthesis Facility, Scripps Research, La Jolla, CA 92037, USA
| | - Michal Domanski
- Department of Chemistry, Scripps Research, La Jolla, CA 92037 USA
| | - Michael A. Schmidt
- Chemical Development, Bristol Myers Squibb Corp., New Brunswick, NJ 08903 USA,Corresponding Author:
| | - Donna G. Blackmond
- Department of Chemistry, Scripps Research, La Jolla, CA 92037 USA,Corresponding Author:
| |
Collapse
|
8
|
Bednářová E, Beck LR, Rovis T, Goldschmid SL, Xie K, Tay NES, Ravetz BD, Li J, Joe CL. Tuning the Electrochemical and Photophysical Properties of Osmium-Based Photoredox Catalysts. Synlett 2022. [DOI: 10.1055/s-0041-1737792] [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: 10/19/2022]
Abstract
AbstractThe use of low-energy deep-red (DR) and near-infrared (NIR) light to excite chromophores enables catalysis to ensue across barriers such as materials and tissues. Herein, we report the detailed photophysical characterization of a library of OsII polypyridyl photosensitizers that absorb low-energy light. By tuning ligand scaffold and electron density, we access a range of synthetically useful excited state energies and redox potentials.1 Introduction1.1 Scope1.2 Measuring Ground-State Redox Potentials1.3 Measuring Photophysical Properties1.4 Synthesis of Osmium Complexes2 Properties of Osmium Complexes2.1 Redox Potentials of Os(L)2-Type Complexes2.2 Redox Potentials of Os(L)3-Type Complexes2.3 UV/Vis Absorption and Emission Spectroscopy3 Conclusions
Collapse
Affiliation(s)
| | | | | | | | | | | | | | - Jun Li
- Chemical Process Development, Bristol Myers Squibb
| | | |
Collapse
|
9
|
Beutner GL, Simmons EM, Ayers S, Bemis CY, Goldfogel MJ, Joe CL, Marshall J, Wisniewski SR. A Process Chemistry Benchmark for sp 2-sp 3 Cross Couplings. J Org Chem 2021; 86:10380-10396. [PMID: 34255510 DOI: 10.1021/acs.joc.1c01073] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
As sp2-sp3 disconnections gain acceptance in the medicinal chemist's toolbox, an increasing number of potential drug candidates containing this motif are moving into the pharmaceutical development pipeline. This raises a new set of questions and challenges around the novel, direct methodologies available for forging these bonds. These questions gain further importance in the context of process chemistry, where the focus is the development of scalable processes that enable the large-scale delivery of clinical supplies. In this paper, we describe our efforts to apply a wide variety of standard, photo-, and electrochemical sp2-sp3 cross-coupling methods to a pharmaceutically relevant intermediate and optimize each through a combination of high throughput and mechanistically guided experimentation. With data regarding the performance, benefits, and limitations of these novel methods, we evaluate them against a more traditional two-step palladium-catalyzed process. This work reveals trends and similarities between these sp2-sp3 bond-forming methods and suggests a path forward for further refinements.
Collapse
Affiliation(s)
- Gregory L Beutner
- Chemical Process Development, Bristol Myers Squibb Company, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Eric M Simmons
- Chemical Process Development, Bristol Myers Squibb Company, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Sloan Ayers
- Chemical Process Development, Bristol Myers Squibb Company, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Christopher Y Bemis
- Chemical Process Development, Bristol Myers Squibb Company, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Matthew J Goldfogel
- Chemical Process Development, Bristol Myers Squibb Company, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Candice L Joe
- Chemical Process Development, Bristol Myers Squibb Company, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Jonathan Marshall
- Chemical Process Development, Bristol Myers Squibb Company, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Steven R Wisniewski
- Chemical Process Development, Bristol Myers Squibb Company, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| |
Collapse
|
10
|
Kuppusamy S, Gangu AS, Kalidindi S, Ponnusamy M, Tendulkar S, Venu A, Palani S, Nagappan V, Vinodini A, Mudryk B, Rupasinghe S, Joe CL, Coombs JR, Gallagher WP, Kopp N, Gonzalez-Bobes F, Eastgate MD, Vaidyanathan R. Development of a Scalable Synthetic Route to BMS-986251. Part 1: Synthesis of the Cyclohexane Dicarboxylate Fragment. Org Process Res Dev 2021. [DOI: 10.1021/acs.oprd.1c00124] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Sankar Kuppusamy
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Aravind S. Gangu
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Srinivas Kalidindi
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Muthukrishnan Ponnusamy
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Shankar Tendulkar
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Alla Venu
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Senthil Palani
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Vedhachalam Nagappan
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Arun Vinodini
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| | - Boguslaw Mudryk
- Chemical Process Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Sanjeewa Rupasinghe
- Chemical Process Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Candice L. Joe
- Chemical Process Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - John R. Coombs
- Chemical Process Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - William P. Gallagher
- Chemical Process Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Nathaniel Kopp
- Chemical Process Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Francisco Gonzalez-Bobes
- Chemical Process Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Martin D. Eastgate
- Chemical Process Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Rajappa Vaidyanathan
- Chemical Development and API Supply, Biocon Bristol-Myers Squibb Research and Development Center, Biocon Park, Jigani Link Road, Bommasandra IV, Bangalore 560099, India
| |
Collapse
|
11
|
Joe CL, Inankur B, Chadwick J, Lou S, Nye J, Strotman NA, DelMonte AJ. Development of a Scalable Negishi Cross-Coupling Process for the Preparation of 2-Chloro-5-(1-(tetrahydro-2 H-pyran-2-yl)-1 H-pyrazol-5-yl)aniline. Org Process Res Dev 2021. [DOI: 10.1021/acs.oprd.0c00414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Candice L. Joe
- Chemical Process Development, Bristol Myers Squibb, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Bahar Inankur
- Chemical Process Development, Bristol Myers Squibb, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - James Chadwick
- Chemical Process Development, Bristol Myers Squibb, Reeds Lane, Moreton, Wirral CH46 1QW, United Kingdom
| | - Sha Lou
- Chemical Process Development, Bristol Myers Squibb, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Jeffrey Nye
- Chemical Process Development, Bristol Myers Squibb, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Neil A. Strotman
- Chemical Process Development, Bristol Myers Squibb, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Albert J. DelMonte
- Chemical Process Development, Bristol Myers Squibb, One Squibb Drive, New Brunswick, New Jersey 08903, United States
| |
Collapse
|
12
|
Ravetz B, Tay NES, Joe CL, Sezen-Edmonds M, Schmidt MA, Tan Y, Janey JM, Eastgate MD, Rovis T. Development of a Platform for Near-Infrared Photoredox Catalysis. ACS Cent Sci 2020; 6:2053-2059. [PMID: 33274281 PMCID: PMC7706074 DOI: 10.1021/acscentsci.0c00948] [Citation(s) in RCA: 75] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Indexed: 05/05/2023]
Abstract
Over the past decade, chemists have embraced visible-light photoredox catalysis due to its remarkable ability to activate small molecules. Broadly, these methods employ metal complexes or organic dyes to convert visible light into chemical energy. Unfortunately, the excitation of widely utilized Ru and Ir chromophores is energetically wasteful as ∼25% of light energy is lost thermally before being quenched productively. Hence, photoredox methodologies require high-energy, intense light to accommodate said catalytic inefficiency. Herein, we report photocatalysts which cleanly convert near-infrared (NIR) and deep red (DR) light into chemical energy with minimal energetic waste. We leverage the strong spin-orbit coupling (SOC) of Os(II) photosensitizers to directly access the excited triplet state (T1) with NIR or DR irradiation from the ground state singlet (S0). Through strategic catalyst design, we access a wide range of photoredox, photopolymerization, and metallaphotoredox reactions which usually require 15-50% higher excitation energy. Finally, we demonstrate superior light penetration and scalability of NIR photoredox catalysis through a mole-scale arene trifluoromethylation in a batch reactor.
Collapse
Affiliation(s)
- Benjamin
D. Ravetz
- Department
of Chemistry, Columbia University, New York, New York 10027, United States
| | - Nicholas E. S. Tay
- Department
of Chemistry, Columbia University, New York, New York 10027, United States
| | - Candice L. Joe
- Chemical
Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
- E-mail:
| | - Melda Sezen-Edmonds
- Chemical
Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Michael A. Schmidt
- Chemical
Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Yichen Tan
- Chemical
Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Jacob M. Janey
- Chemical
Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Martin D. Eastgate
- Chemical
Process Development, Bristol Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Tomislav Rovis
- Department
of Chemistry, Columbia University, New York, New York 10027, United States
- E-mail:
| |
Collapse
|
13
|
Vasquez AM, Gurak JA, Joe CL, Cherney EC, Engle KM. Catalytic α-Hydroarylation of Acrylates and Acrylamides via an Interrupted Hydrodehalogenation Reaction. J Am Chem Soc 2020; 142:10477-10484. [PMID: 32379433 PMCID: PMC7293711 DOI: 10.1021/jacs.0c03040] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The palladium-catalyzed, α-selective hydroarylation of acrylates and acrylamides is reported. Under optimized conditions, this method is highly tolerant of a wide range of substrates including those with base sensitive functional groups and/or multiple enolizable carbonyl groups. A detailed mechanistic study was undertaken, and the high selectivity of this transformation was shown to be enabled by the formation of a [PdII(Ar)(H)] intermediate, which performs selective hydride insertion into the β-position of α,β-unsaturated carbonyl compounds.
Collapse
Affiliation(s)
- Alena M. Vasquez
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - John A. Gurak
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| | - Candice L. Joe
- Chemistry Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, New Jersey 08903, United States
| | - Emily C. Cherney
- Discovery Chemistry, Bristol Myers Squibb, US Rt. 206 & Province Line Road, Princeton, New Jersey 08540, United States
| | - Keary M. Engle
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
| |
Collapse
|
14
|
Zhuang Z, Yu CB, Chen G, Wu QF, Hsiao Y, Joe CL, Qiao JX, Poss MA, Yu JQ. Ligand-Enabled β-C(sp 3)-H Olefination of Free Carboxylic Acids. J Am Chem Soc 2018; 140:10363-10367. [PMID: 30029574 DOI: 10.1021/jacs.8b06527] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
An acetyl-protected aminoethyl phenyl thioether has been developed to promote C(sp3)-H activation. Significant ligand enhancement is demonstrated by the realization of the first Pd(II)-catalyzed olefination of C(sp3)-H bonds of free carboxylic acids without using an auxiliary. Subsequent lactonization of the olefinated product via 1,4 addition provided exclusively monoselectivity in the presence of multiple β-C-H bonds. The product γ-lactone can be readily opened to give either the highly valuable β-olefinated or γ-hydroxylated aliphatic acids. Considering the challenges in developing Heck couplings using alkyl halides, this reaction offers a useful alternative.
Collapse
Affiliation(s)
- Zhe Zhuang
- Department of Chemistry , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Chang-Bin Yu
- Department of Chemistry , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Gang Chen
- Department of Chemistry , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Qing-Feng Wu
- Department of Chemistry , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| | - Yi Hsiao
- Chemical and Synthetic Development , Bristol-Myers Squibb , 1 Squibb Drive , New Brunswick , New Jersey 08903 , United States
| | - Candice L Joe
- Chemical and Synthetic Development , Bristol-Myers Squibb , 1 Squibb Drive , New Brunswick , New Jersey 08903 , United States
| | - Jennifer X Qiao
- Discovery Chemistry , Bristol-Myers Squibb Company , P.O. Box 4000, Princeton , New Jersey 08543 , United States
| | - Michael A Poss
- Discovery Chemistry , Bristol-Myers Squibb Company , P.O. Box 4000, Princeton , New Jersey 08543 , United States
| | - Jin-Quan Yu
- Department of Chemistry , The Scripps Research Institute , 10550 North Torrey Pines Road , La Jolla , California 92037 , United States
| |
Collapse
|
15
|
Chen G, Zhuang Z, Li GC, Saint-Denis TG, Hsiao Y, Joe CL, Yu JQ. Ligand-Enabled β-C-H Arylation of α-Amino Acids Without Installing Exogenous Directing Groups. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201610580] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Gang Chen
- Department of Chemistry; The Scripps Research Institute (TSRI); 10550 North Torrey Pines Road La Jolla CA 92037 USA
| | - Zhe Zhuang
- Department of Chemistry; The Scripps Research Institute (TSRI); 10550 North Torrey Pines Road La Jolla CA 92037 USA
| | - Gen-Cheng Li
- Department of Chemistry; The Scripps Research Institute (TSRI); 10550 North Torrey Pines Road La Jolla CA 92037 USA
| | - Tyler G. Saint-Denis
- Department of Chemistry; The Scripps Research Institute (TSRI); 10550 North Torrey Pines Road La Jolla CA 92037 USA
| | - Yi Hsiao
- Chemical and Synthetic Development; Bristol-Myers Squibb; 1 Squibb Drive New Brunswick NJ 08903 USA
| | - Candice L. Joe
- Chemical and Synthetic Development; Bristol-Myers Squibb; 1 Squibb Drive New Brunswick NJ 08903 USA
| | - Jin-Quan Yu
- Department of Chemistry; The Scripps Research Institute (TSRI); 10550 North Torrey Pines Road La Jolla CA 92037 USA
| |
Collapse
|
16
|
Chen G, Zhuang Z, Li GC, Saint-Denis TG, Hsiao Y, Joe CL, Yu JQ. Ligand-Enabled β-C-H Arylation of α-Amino Acids Without Installing Exogenous Directing Groups. Angew Chem Int Ed Engl 2017; 56:1506-1509. [PMID: 28052530 DOI: 10.1002/anie.201610580] [Citation(s) in RCA: 99] [Impact Index Per Article: 14.1] [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: 10/28/2016] [Indexed: 11/09/2022]
Abstract
Herein we report acid-directed β-C(sp3 )-H arylation of α-amino acids enabled by pyridine-type ligands. This reaction does not require the installation of an exogenous directing group, is scalable, and enables the preparation of Fmoc-protected unnatural amino acids in three steps. The pyridine-type ligands are crucial for the development of this new C(sp3 )-H arylation.
Collapse
Affiliation(s)
- Gang Chen
- Department of Chemistry, The Scripps Research Institute (TSRI), 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Zhe Zhuang
- Department of Chemistry, The Scripps Research Institute (TSRI), 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Gen-Cheng Li
- Department of Chemistry, The Scripps Research Institute (TSRI), 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Tyler G Saint-Denis
- Department of Chemistry, The Scripps Research Institute (TSRI), 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
| | - Yi Hsiao
- Chemical and Synthetic Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, NJ, 08903, USA
| | - Candice L Joe
- Chemical and Synthetic Development, Bristol-Myers Squibb, 1 Squibb Drive, New Brunswick, NJ, 08903, USA
| | - Jin-Quan Yu
- Department of Chemistry, The Scripps Research Institute (TSRI), 10550 North Torrey Pines Road, La Jolla, CA, 92037, USA
| |
Collapse
|
17
|
Abstract
Using nickel and photoredox catalysis, the direct functionalization of C(sp(3))-H bonds of N-aryl amines by acyl electrophiles is described. The method affords a diverse range of α-amino ketones at room temperature and is amenable to late-stage coupling of complex and biologically relevant groups. C(sp(3))-H activation occurs by photoredox-mediated oxidation to generate α-amino radicals which are intercepted by nickel in catalytic C(sp(3))-C coupling. The merger of these two modes of catalysis leverages nickel's unique properties in alkyl cross-coupling while avoiding limitations commonly associated with transition-metal-mediated C(sp(3))-H activation, including requirements for chelating directing groups and high reaction temperatures.
Collapse
Affiliation(s)
- Candice L Joe
- Department of Chemistry, Princeton University, 120 Washington Road, Princeton, NJ, 08544, USA
| | - Abigail G Doyle
- Department of Chemistry, Princeton University, 120 Washington Road, Princeton, NJ, 08544, USA.
| |
Collapse
|
18
|
Affiliation(s)
- Candice L. Joe
- Department of Chemistry; Princeton University; 120 Washington Road Princeton NJ 08544 USA
| | - Abigail G. Doyle
- Department of Chemistry; Princeton University; 120 Washington Road Princeton NJ 08544 USA
| |
Collapse
|
19
|
Abstract
In hydroformylation, phosphorus-based directing groups have been consistently successful at placing the aldehyde on the carbon proximal to the directing group. The design and synthesis of a novel catalytic directing group are reported that promotes aldehyde formation on the carbon distal relative to the directing functionality. This scaffolding ligand, which operates through a reversible covalent bond to the substrate, has been applied to the diastereoselective hydroformylation of homoallylic alcohols to afford δ-lactones selectively. Altering the distance between the alcohol and the olefin revealed that homoallylic alcohols gives the distal lactone with the highest levels of regioselectivity.
Collapse
Affiliation(s)
- Candice L Joe
- Department of Chemistry, Merkert Chemistry Center, Boston College , Chestnut Hill, Massachusetts 02467, United States
| | | | | | | |
Collapse
|
20
|
Klein AH, Joe CL, Davoodi A, Takechi K, Carstens MI, Carstens E. Eugenol and carvacrol excite first- and second-order trigeminal neurons and enhance their heat-evoked responses. Neuroscience 2014; 271:45-55. [PMID: 24759772 DOI: 10.1016/j.neuroscience.2014.04.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [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: 12/06/2013] [Revised: 04/08/2014] [Accepted: 04/09/2014] [Indexed: 12/30/2022]
Abstract
Eugenol and carvacrol from clove and oregano, respectively, are agonists of the warmth-sensitive transient receptor potential channel TRPV3 and the irritant-sensitive transient receptor potential ankyrin (TRPA)-1. Eugenol and carvacrol induce oral irritation that rapidly desensitizes, accompanied by brief enhancement of innocuous warmth and heat pain in humans. We presently investigated if eugenol and carvacrol activate nociceptive primary afferent and higher order trigeminal neurons and enhance their heat-evoked responses, using calcium imaging of cultured trigeminal ganglion (TG) and dorsal root ganglion (DRG) neurons, and in vivo single-unit recordings in trigeminal subnucleus caudalis (Vc) of rats. Eugenol and carvacrol activated 20-30% of TG and 7-20% of DRG cells, the majority of which additionally responded to menthol, mustard oil and/or capsaicin. TG cell responses to innocuous (39°) and noxious (42 °C) heating were enhanced by eugenol and carvacrol. We identified dorsomedial Vc neurons responsive to noxious heating of the tongue in pentobarbital-anesthetized rats. Eugenol and carvacrol dose-dependently elicited desensitizing responses in 55% and 73% of heat-sensitive units, respectively. Responses to noxious heat were briefly enhanced by eugenol and carvacrol. Many eugenol- and carvacrol-responsive units also responded to menthol, cinnamaldehyde and capsaicin. These data support a peripheral site for eugenol and carvacrol to enhance warmth- and noxious heat-evoked responses of trigeminal neurons, and are consistent with the observation that these agonists briefly enhance warmth and heat pain on the human tongue.
Collapse
Affiliation(s)
- A H Klein
- Department of Neurobiology, Physiology and Behavior, University of California, 1 Shields Avenue, Davis, CA 95616, USA
| | - C L Joe
- Department of Neurobiology, Physiology and Behavior, University of California, 1 Shields Avenue, Davis, CA 95616, USA
| | - A Davoodi
- Department of Neurobiology, Physiology and Behavior, University of California, 1 Shields Avenue, Davis, CA 95616, USA
| | - K Takechi
- Department of Neurobiology, Physiology and Behavior, University of California, 1 Shields Avenue, Davis, CA 95616, USA
| | - M I Carstens
- Department of Neurobiology, Physiology and Behavior, University of California, 1 Shields Avenue, Davis, CA 95616, USA
| | - E Carstens
- Department of Neurobiology, Physiology and Behavior, University of California, 1 Shields Avenue, Davis, CA 95616, USA.
| |
Collapse
|
21
|
Liu R, Yuan G, Joe CL, Lightburn TE, Tan KL, Wang D. Titelbild: Silicon Nanowires as Photoelectrodes for Carbon Dioxide Fixation (Angew. Chem. 27/2012). Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201204212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
22
|
Liu R, Yuan G, Joe CL, Lightburn TE, Tan KL, Wang D. Silicon nanowires as photoelectrodes for carbon dioxide fixation. Angew Chem Int Ed Engl 2012; 51:6709-12. [PMID: 22615263 PMCID: PMC3480189 DOI: 10.1002/anie.201202569] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2012] [Indexed: 01/06/2023]
Affiliation(s)
| | | | - Candice L. Joe
- Merkert Chemistry Center, Department of Chemistry, Boston College, 2609 Beacon St. Chestnut Hill, MA, USA 02467
| | - Thomas E. Lightburn
- Merkert Chemistry Center, Department of Chemistry, Boston College, 2609 Beacon St. Chestnut Hill, MA, USA 02467
| | - Kian L. Tan
- Merkert Chemistry Center, Department of Chemistry, Boston College, 2609 Beacon St. Chestnut Hill, MA, USA 02467
| | - Dunwei Wang
- Merkert Chemistry Center, Department of Chemistry, Boston College, 2609 Beacon St. Chestnut Hill, MA, USA 02467
| |
Collapse
|
23
|
Liu R, Yuan G, Joe CL, Lightburn TE, Tan KL, Wang D. Cover Picture: Silicon Nanowires as Photoelectrodes for Carbon Dioxide Fixation (Angew. Chem. Int. Ed. 27/2012). Angew Chem Int Ed Engl 2012. [DOI: 10.1002/anie.201204212] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
24
|
|
25
|
Abstract
We have developed a ligand that reversibly binds to aniline substrates, allowing for the control of regioselectivity and enantioselectivity in hydroformylation. In this paper we address how the electronics of the aniline ring affect both the binding of the substrate to the ligand and the enantioselectivity in this reaction.
Collapse
Affiliation(s)
- Candice L Joe
- Boston College, 2609 Beacon Street, Chestnut Hill, Massachusetts 02467-3860, USA
| | | |
Collapse
|
26
|
Abstract
The synthesis of β-amino-aldehydes has been achieved through enantioselective hydroformylation of PMP-protected allylic amines. The reaction is accomplished by using a scalemic scaffolding ligand that covalently and reversibly binds to the substrate. These ligands behave like chiral auxiliaries because they are covalently attached to the substrate during hydroformylation; however, similar to traditional asymmetric ligands, they can be used in catalytic quantities. The directed hydroformylation of disubstituted olefins occurs under mild conditions (35 °C and 50 psi CO/H(2)), and Z-olefins afford excellent enantioselectivities (up to 93% ee).
Collapse
Affiliation(s)
| | | | - Thomas E. Lightburn
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467
| | - Kian L. Tan
- Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, Massachusetts 02467
| |
Collapse
|