1
|
Trauner F, Ghazali R, Rettig J, Thiele CM, Didier D. Stereoselective polar radical crossover for the functionalization of strained-ring systems. Commun Chem 2024; 7:139. [PMID: 38898159 PMCID: PMC11187220 DOI: 10.1038/s42004-024-01221-3] [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] [Received: 01/18/2024] [Accepted: 06/06/2024] [Indexed: 06/21/2024] Open
Abstract
Radical-polar crossover of organoborates is a poweful tool that enables the creation of two C-C bonds simultaneously. Small ring systems have become essential motifs in drug discovery and medicinal chemistry. However, step-economic methods for their selective functionalization remains scarce. Here we present a one-pot strategy that merges a simple preparation of strained organoboron species with the recently popularized polar radical crossover of borate derivatives to stereoselectively access tri-substituted azetidines, cyclobutanes and five-membered carbo- and heterocycles.
Collapse
Affiliation(s)
- Florian Trauner
- Technische Universität Darmstadt, Clemens-Schöpf-Insitut für Organische Chemie und Biochemie, Peter-Grünberg-Str. 4, 64287, Darmstadt, Germany
- Ludwig-Maximilians Universität, Department Chemie, Butenandtstr. 5, 81377, München, Germany
| | - Rahma Ghazali
- Technische Universität Darmstadt, Clemens-Schöpf-Insitut für Organische Chemie und Biochemie, Peter-Grünberg-Str. 4, 64287, Darmstadt, Germany
| | - Jan Rettig
- Technische Universität Darmstadt, Clemens-Schöpf-Insitut für Organische Chemie und Biochemie, Peter-Grünberg-Str. 4, 64287, Darmstadt, Germany
| | - Christina M Thiele
- Technische Universität Darmstadt, Clemens-Schöpf-Insitut für Organische Chemie und Biochemie, Peter-Grünberg-Str. 4, 64287, Darmstadt, Germany
| | - Dorian Didier
- Technische Universität Darmstadt, Clemens-Schöpf-Insitut für Organische Chemie und Biochemie, Peter-Grünberg-Str. 4, 64287, Darmstadt, Germany.
- Ludwig-Maximilians Universität, Department Chemie, Butenandtstr. 5, 81377, München, Germany.
| |
Collapse
|
2
|
Hanania N, Eghbarieh N, Masarwa A. PolyBorylated Alkenes as Energy-Transfer Reactive Groups: Access to Multi-Borylated Cyclobutanes Combined with Hydrogen Atom Transfer Event. Angew Chem Int Ed Engl 2024; 63:e202405898. [PMID: 38603554 DOI: 10.1002/anie.202405898] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 04/11/2024] [Accepted: 04/11/2024] [Indexed: 04/13/2024]
Abstract
While polyborylated alkenes are being recognized for their elevated status as highly valuable reagents in modern organic synthesis, allowing efficient access to a diverse array of transformations, including the formation of C-C and C-heteroatom bonds, their potential as energy-transfer reactive groups has remained unexplored. Yet, this potential holds the key to generating elusive polyborylated biradical species, which can be captured by olefins, thereby leading to the construction of new highly-borylated scaffolds. Herein, we report a designed energy-transfer strategy for photosensitized [2+2]-cycloadditions of poly-borylated alkenes with various olefins enabling the regioselective synthesis of diverse poly-borylated cyclobutane motifs, including the 1,1-di-, 1,1,2-tri-, and 1,1,2,2-tetra-borylated cyclobutanes. In fact, these compounds belong to a family that presently lacks efficient synthetic pathways. Interestingly, when α-methylstyrene was used, the reaction involves an interesting 1,5-hydrogen atom transfer (HAT). Mechanistic deuterium-labeling studies have provided insight into the outcome of 1,5-hydrogen atom transfer process. In addition, the polyborylated cyclobutanes are then demonstrated to be useful in selective oxidation processes resulting in the formation of cyclobutanones and γ-lactones.
Collapse
Affiliation(s)
- Nicole Hanania
- Institute of Chemistry, The Center for Nanoscience and Nanotechnology, and Casali Center for Applied Chemistry, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Nadim Eghbarieh
- Institute of Chemistry, The Center for Nanoscience and Nanotechnology, and Casali Center for Applied Chemistry, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| | - Ahmad Masarwa
- Institute of Chemistry, The Center for Nanoscience and Nanotechnology, and Casali Center for Applied Chemistry, The Hebrew University of Jerusalem, Jerusalem, 9190401, Israel
| |
Collapse
|
3
|
Hou SY, Yan BC, Sun HD, Puno PT. Recent advances in the application of [2 + 2] cycloaddition in the chemical synthesis of cyclobutane-containing natural products. NATURAL PRODUCTS AND BIOPROSPECTING 2024; 14:37. [PMID: 38861197 PMCID: PMC11166626 DOI: 10.1007/s13659-024-00457-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Accepted: 05/24/2024] [Indexed: 06/12/2024]
Abstract
Cyclobutanes are distributed widely in a large class of natural products featuring diverse pharmaceutical activities and intricate structural frameworks. The [2 + 2] cycloaddition is unequivocally the primary and most commonly used method for synthesizing cyclobutanes. In this review, we have summarized the application of the [2 + 2] cycloaddition with different reaction mechanisms in the chemical synthesis of selected cyclobutane-containing natural products over the past decade.
Collapse
Affiliation(s)
- Song-Yu Hou
- Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Kunming, 650201, Yunnan, People's Republic of China
| | - Bing-Chao Yan
- Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Kunming, 650201, Yunnan, People's Republic of China
| | - Han-Dong Sun
- Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Kunming, 650201, Yunnan, People's Republic of China
| | - Pema-Tenzin Puno
- Key Laboratory of Phytochemistry and Natural Medicines, Kunming Institute of Botany, University of Chinese Academy of Sciences, Chinese Academy of Sciences, Kunming, 650201, Yunnan, People's Republic of China.
| |
Collapse
|
4
|
Plachinski EF, Kim HJ, Genzink MJ, Sanders KM, Kelch RM, Guzei IA, Yoon TP. A General Synthetic Strategy toward the Truxillate Natural Products via Solid-State Photocycloadditions. J Am Chem Soc 2024; 146:14948-14953. [PMID: 38775350 PMCID: PMC11167107 DOI: 10.1021/jacs.4c04706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
The truxillates constitute a large class of dimeric natural products featuring a central, highly substituted cyclobutane core. In principle, these structures could be efficiently synthesized via [2 + 2] photocycloaddition. However, the difficulty in controlling the high-energy electronically excited reactive intermediates in the solution state can lead to poor regio- and diastereocontrol. This has limited the use of photocycloaddition methodology toward the synthesis of this important class of natural products. Herein, we demonstrate that acid-controlled precipitation of C-acyl imidazoles promotes a highly selective solid-state photocycloaddition, and the products of this reaction can be quickly transformed into truxillate natural products.
Collapse
Affiliation(s)
- Ellie F. Plachinski
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, WI 53706, USA
| | - Hyung Joo Kim
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, WI 53706, USA
| | - Matthew J. Genzink
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, WI 53706, USA
| | - Kyana M. Sanders
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, WI 53706, USA
- Molecular Structure Laboratory, Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, WI 53706, USA
| | - Riley M. Kelch
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, WI 53706, USA
- Molecular Structure Laboratory, Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, WI 53706, USA
| | - Ilia A. Guzei
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, WI 53706, USA
- Molecular Structure Laboratory, Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, WI 53706, USA
| | - Tehshik P. Yoon
- Department of Chemistry, University of Wisconsin–Madison, 1101 University Avenue, Madison, WI 53706, USA
| |
Collapse
|
5
|
McVeigh MS, Sorrentino JP, Hands AT, Garg NK. Access to Complex Scaffolds Through [2 + 2] Cycloadditions of Strained Cyclic Allenes. J Am Chem Soc 2024; 146:15420-15427. [PMID: 38768558 DOI: 10.1021/jacs.4c03369] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2024]
Abstract
We report the strain-induced [2 + 2] cycloadditions of cyclic allenes for the assembly of highly substituted cyclobutanes. By judicious choice of trapping agent, complex scaffolds bearing heteroatoms, fused rings, contiguous stereocenters, spirocycles, and quaternary centers are ultimately accessible. Moreover, we show that the resulting cycloadducts can undergo thermal isomerization. This study provides an alternative strategy to photochemical [2 + 2] cycloadditions for accessing highly functionalized cyclobutanes, while validating the use of underexplored strained intermediates for the assembly of complex architectures.
Collapse
Affiliation(s)
- Matthew S McVeigh
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Jacob P Sorrentino
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Allison T Hands
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Neil K Garg
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| |
Collapse
|
6
|
Posz JM, Sharma N, Royalty PA, Liu Y, Salome C, Fessard TC, Brown MK. Synthesis of Borylated Carbocycles by [2 + 2]-Cycloadditions and Photo-Ene Reactions. J Am Chem Soc 2024; 146:10142-10149. [PMID: 38536870 PMCID: PMC11041674 DOI: 10.1021/jacs.4c01557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/11/2024]
Abstract
Saturated bicyclic compounds make up a valuable class of building blocks in the development of agrochemicals and pharmaceuticals. Here, we present the synthesis of borylated bicyclo[2.1.1]hexanes via crossed [2 + 2]-cycloaddition. Due to the presence of the C-B bond, a variety of structures can be easily prepared that are not accessible by other methods. Moreover, a rare photo-ene reaction is also disclosed, allowing for the diastereoselective synthesis of trisubstituted borylated cyclopentanes.
Collapse
Affiliation(s)
- Jarett M Posz
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Neetu Sharma
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Paige A Royalty
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Yanyao Liu
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| | - Christophe Salome
- SpiroChem AG, Rosental Area, WRO-1047-3, Mattenstrasse 22, Basel 4058, Switzerland
| | - Thomas C Fessard
- SpiroChem AG, Rosental Area, WRO-1047-3, Mattenstrasse 22, Basel 4058, Switzerland
| | - M Kevin Brown
- Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, Indiana 47405, United States
| |
Collapse
|
7
|
Dutta S, Lu YL, Erchinger JE, Shao H, Studer E, Schäfer F, Wang H, Rana D, Daniliuc CG, Houk KN, Glorius F. Double Strain-Release [2π+2σ]-Photocycloaddition. J Am Chem Soc 2024; 146:5232-5241. [PMID: 38350439 DOI: 10.1021/jacs.3c11563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2024]
Abstract
In pursuit of potent pharmaceutical candidates and to further improve their chemical traits, small ring systems can serve as a potential starting point. Small ring units have the additional merit of loaded strain at their core, making them suitable reactants as they can capitalize on this intrinsic driving force. With the introduction of cyclobutenone as a strained precursor to ketene, the photocycloaddition with another strained unit, bicyclo[1.1.0]butane (BCB), enables the reactivity of both π-units in the transient ketene. This double strain-release driven [2π+2σ]-photocycloaddition promotes the synthesis of diverse heterobicyclo[2.1.1]hexane units, a pharmaceutically relevant bioisostere. The effective reactivity under catalyst-free conditions with a high functional group tolerance defines its synthetic utility. Experimental mechanistic studies and density functional theory (DFT) calculations suggest that the [2π+2σ]-photocycloaddition takes place via a triplet mechanism.
Collapse
Affiliation(s)
- Subhabrata Dutta
- Organisch-Chemisches Institut, Universität Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Yi-Lin Lu
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Johannes E Erchinger
- Organisch-Chemisches Institut, Universität Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Huiling Shao
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Emanuel Studer
- Organisch-Chemisches Institut, Universität Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Felix Schäfer
- Organisch-Chemisches Institut, Universität Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Huamin Wang
- Organisch-Chemisches Institut, Universität Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Debanjan Rana
- Organisch-Chemisches Institut, Universität Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Universität Münster, Corrensstraße 36, 48149 Münster, Germany
| | - K N Houk
- Department of Chemistry and Biochemistry, University of California, Los Angeles, California 90095, United States
| | - Frank Glorius
- Organisch-Chemisches Institut, Universität Münster, Corrensstraße 36, 48149 Münster, Germany
| |
Collapse
|
8
|
Prysiazhniuk K, Polishchuk O, Shulha S, Gudzikevych K, Datsenko OP, Kubyshkin V, Mykhailiuk PK. Borylated cyclobutanes via thermal [2 + 2]-cycloaddition. Chem Sci 2024; 15:3249-3254. [PMID: 38425521 PMCID: PMC10901489 DOI: 10.1039/d3sc06600b] [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: 12/08/2023] [Accepted: 01/17/2024] [Indexed: 03/02/2024] Open
Abstract
A one-step approach to borylated cyclobutanes from amides of carboxylic acids and vinyl boronates is elaborated. The reaction proceeds via the thermal [2 + 2]-cycloaddition of in situ-generated keteniminium salts.
Collapse
Affiliation(s)
- Kateryna Prysiazhniuk
- Enamine Ltd Winston Churchill St. 78 02094 Kyiv Ukraine https://www.mykhailiukchem.org
| | - Oleksandr Polishchuk
- Enamine Ltd Winston Churchill St. 78 02094 Kyiv Ukraine https://www.mykhailiukchem.org
| | - Stanislav Shulha
- Enamine Ltd Winston Churchill St. 78 02094 Kyiv Ukraine https://www.mykhailiukchem.org
| | - Kyrylo Gudzikevych
- Enamine Ltd Winston Churchill St. 78 02094 Kyiv Ukraine https://www.mykhailiukchem.org
| | - Oleksandr P Datsenko
- Enamine Ltd Winston Churchill St. 78 02094 Kyiv Ukraine https://www.mykhailiukchem.org
| | - Vladimir Kubyshkin
- Enamine Ltd Winston Churchill St. 78 02094 Kyiv Ukraine https://www.mykhailiukchem.org
| | - Pavel K Mykhailiuk
- Enamine Ltd Winston Churchill St. 78 02094 Kyiv Ukraine https://www.mykhailiukchem.org
| |
Collapse
|
9
|
Dutta S, Erchinger JE, Strieth-Kalthoff F, Kleinmans R, Glorius F. Energy transfer photocatalysis: exciting modes of reactivity. Chem Soc Rev 2024; 53:1068-1089. [PMID: 38168974 DOI: 10.1039/d3cs00190c] [Citation(s) in RCA: 24] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Excited (triplet) states offer a myriad of attractive synthetic pathways, including cycloadditions, selective homolytic bond cleavages and strain-release chemistry, isomerizations, deracemizations, or the fusion with metal catalysis. Recent years have seen enormous advantages in enabling these reactivity modes through visible-light-mediated triplet-triplet energy transfer catalysis (TTEnT). This tutorial review provides an overview of this emerging strategy for synthesizing sought-after organic motifs in a mild, selective, and sustainable manner. Building on the photophysical foundations of energy transfer, this review also discusses catalyst design, as well as the challenges and opportunities of energy transfer catalysis.
Collapse
Affiliation(s)
- Subhabrata Dutta
- University of Münster, Organisch-Chemisches Institut, Corrensstraße 36, 48149 Münster, Germany.
| | - Johannes E Erchinger
- University of Münster, Organisch-Chemisches Institut, Corrensstraße 36, 48149 Münster, Germany.
| | - Felix Strieth-Kalthoff
- University of Münster, Organisch-Chemisches Institut, Corrensstraße 36, 48149 Münster, Germany.
| | - Roman Kleinmans
- University of Münster, Organisch-Chemisches Institut, Corrensstraße 36, 48149 Münster, Germany.
| | - Frank Glorius
- University of Münster, Organisch-Chemisches Institut, Corrensstraße 36, 48149 Münster, Germany.
| |
Collapse
|
10
|
Liu Y, Brown MK. Photosensitized [2 + 2]-Cycloadditions of Dioxaborole: Reactivity Enabled by Boron Ring Constraint Strategy. J Am Chem Soc 2023; 145:25061-25067. [PMID: 37939224 PMCID: PMC11041673 DOI: 10.1021/jacs.3c08105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2023]
Abstract
A strategy to achieve photosensitized [2 + 2] cycloadditions by means of temporary ring constraint is reported. Specifically, a dioxaborole is prepared that undergoes [2 + 2] cycloadditions with a wide variety of alkenes. This strategy overcomes some challenges with the cycloaddition of acyclic substrates. The products can be easily transformed into cyclobutyl diols or 1,4-dicarbonyl compounds; the latter represents a formal alkene vicinal diacylation. The synthetic utility of this method is shown in the synthesis of valuable heterocycles and biatriosporin D.
Collapse
Affiliation(s)
- Yanyao Liu
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, Indiana 47405, United States
| | - M Kevin Brown
- Department of Chemistry, Indiana University, 800 E. Kirkwood Ave., Bloomington, Indiana 47405, United States
| |
Collapse
|
11
|
Wang H, Erchinger JE, Lenz M, Dutta S, Daniliuc CG, Glorius F. syn-Selective Difunctionalization of Bicyclobutanes Enabled by Photoredox-Mediated C-S σ-Bond Scission. J Am Chem Soc 2023; 145:23771-23780. [PMID: 37852210 DOI: 10.1021/jacs.3c08512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2023]
Abstract
Given the importance of cyclic frameworks in molecular scaffolds and drug discovery, it is intriguing to precisely forge and manipulate ring systems in synthetic chemistry. In this field, the intermolecular synthesis of densely substituted cyclobutanes with precise diastereocontrol under simple reaction conditions remains a challenge. Herein, a photoredox strategy for the difunctionalization of bicyclo[1.1.0]butanes (BCBs) under high regio- and syn-selectivity is disclosed. C-S σ-bond cleavage of partially unsaturated sulfur-containing bifunctional reagents in an overall strain-release-driven process enables the thio-alkynylation, -alkenylation, and -allylation of BCBs under mild conditions and demonstrates the generality of this protocol. Mechanistic studies suggest that the intermediacy of cyclic distonic radical cations might be key for the efficient scission of C-S σ-bonds and the origin of diastereoselectivity.
Collapse
Affiliation(s)
- Huamin Wang
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Johannes E Erchinger
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Madina Lenz
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Subhabrata Dutta
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Constantin G Daniliuc
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149 Münster, Germany
| | - Frank Glorius
- Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstraße 36, 48149 Münster, Germany
| |
Collapse
|
12
|
Brals J, McGuire TM, Watson AJB. A Chemoselective Polarity-Mismatched Photocatalytic C(sp 3 )-C(sp 2 ) Cross-Coupling Enabled by Synergistic Boron Activation. Angew Chem Int Ed Engl 2023; 62:e202310462. [PMID: 37622419 PMCID: PMC10952440 DOI: 10.1002/anie.202310462] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 08/21/2023] [Accepted: 08/24/2023] [Indexed: 08/26/2023]
Abstract
We report the development of a C(sp3 )-C(sp2 ) coupling reaction using styrene boronic acids and redox-active esters under photoredox catalysis. The reaction proceeds through an unusual polarity-mismatched radical addition mechanism that is orthogonal to established processes. Synergistic activation of the radical precursor and organoboron are critical mechanistic events. Activation of an N-hydroxyphthalimide (NHPI) ester by coordination to boron enables electron transfer, with decomposition leading to a nucleofuge rebound, activating the organoboron to radical addition. The unique mechanism enables chemoselective coupling of styrene boronic acids in the presence of other alkene radical acceptors. The scope and limitations of the reaction, and a detailed mechanistic investigation are presented.
Collapse
Affiliation(s)
- Jeremy Brals
- EaStCHEMSchool of ChemistryUniversity of St AndrewsPurdie Building, North HaughSt AndrewsKY16 9STUK
| | - Thomas M. McGuire
- AstraZenecaDarwin Building, Unit 310Cambridge Science Park, Milton RoadCambridgeCB4 0WGUK
| | - Allan J. B. Watson
- EaStCHEMSchool of ChemistryUniversity of St AndrewsPurdie Building, North HaughSt AndrewsKY16 9STUK
| |
Collapse
|
13
|
Liashuk OS, Grygorenko OO, Volovenko YM, Waser J. Photochemical [2+2] Cycloaddition of Alkynyl Boronates. Chemistry 2023; 29:e202301650. [PMID: 37394686 DOI: 10.1002/chem.202301650] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 06/30/2023] [Accepted: 06/30/2023] [Indexed: 07/04/2023]
Abstract
A photochemical [2+2] cycloaddition of alkynyl boronates and maleimides is reported. The developed protocol provided 35-70 % yield of maleimide-derived cyclobutenyl boronates and demonstrated wide compatibility with various functional groups. The synthetic utility of the prepared building blocks was demonstrated for a range of transformations, including Suzuki cross-coupling, catalytic or metal-hydride reduction, oxidation, and cycloaddition reactions. With aryl-substituted alkynyl boronates, the products of double [2+2] cycloaddition were obtained predominantly. Using the developed protocol, a cyclobutene-derived analogue of Thalidomide was prepared in one step. Mechanistic studies supported the participation of the triplet-excited state maleimides and ground state alkynyl boronates in the key step of the process.
Collapse
Affiliation(s)
- Oleksandr S Liashuk
- Chemical Faculty, Taras Shevchenko National University of Kyїv, Kyiv, Volodymyrska Street 60, 01601, Kyїv, Ukraine
- Laboratory of Catalysis and Organic Synthesis, Institut des Sciences et Ingénierie Chimique, Ecole Polytechnique Fédérale de Lausanne, 1015, Lausanne, Switzerland
- Enamine Ltd., Kyiv, Winston Churchill Street 78, 02094, Kyїv, Ukraine
| | - Oleksandr O Grygorenko
- Chemical Faculty, Taras Shevchenko National University of Kyїv, Kyiv, Volodymyrska Street 60, 01601, Kyїv, Ukraine
- Enamine Ltd., Kyiv, Winston Churchill Street 78, 02094, Kyїv, Ukraine
| | - Yulian M Volovenko
- Chemical Faculty, Taras Shevchenko National University of Kyїv, Kyiv, Volodymyrska Street 60, 01601, Kyїv, Ukraine
| | - Jérôme Waser
- Laboratory of Catalysis and Organic Synthesis, Institut des Sciences et Ingénierie Chimique, Ecole Polytechnique Fédérale de Lausanne, 1015, Lausanne, Switzerland
| |
Collapse
|
14
|
Zhao H, Lin Y, Jiang M, Su B. A general catalytic synthetic strategy for highly strained methylenecyclobutanes and spiromethylenecyclobutanes. Chem Sci 2023; 14:7897-7904. [PMID: 37502320 PMCID: PMC10370550 DOI: 10.1039/d3sc01103h] [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: 02/28/2023] [Accepted: 06/09/2023] [Indexed: 07/29/2023] Open
Abstract
Highly strained methylenecyclobutanes (MCBs) are intriguing scaffolds in synthetic chemistry and drug discovery, but there is no such strategy that enables the synthesis of structurally diverse MCBs with defined stereochemistry. We report a general synthetic strategy for (boromethylene)cyclobutanes (BMCBs) and spiro-BMCBs by a challenging Cu-catalyzed highly chemo-, stereo-, and regioselective borylative cyclization of aliphatic alkynes. This strategy not only enables the installation of various functionalities at each site on the MCB skeleton with unambiguous stereochemistry but also introduces a versatile boromethylene unit that is readily transformable to a wide range of new functional groups; these features significantly expand the structural diversity of MCBs and are particularly valuable in drug discovery. The concise and divergent total syntheses of four cyclobutane-containing natural products were achieved from one common BMCB obtained by this strategy. The origin of the high regioselectivity in the borylcupration of alkynes and the high efficiency of the strained ring cyclization was also studied.
Collapse
Affiliation(s)
- Haotian Zhao
- State Key Laboratory of Medical Chemical Biology, College of Pharmacy, Nankai University 38 Tongyan Road, Jinnan District Tianjin 300350 P. R. China
| | - Yu Lin
- State Key Laboratory of Medical Chemical Biology, College of Pharmacy, Nankai University 38 Tongyan Road, Jinnan District Tianjin 300350 P. R. China
| | - Mingyu Jiang
- State Key Laboratory of Medical Chemical Biology, College of Pharmacy, Nankai University 38 Tongyan Road, Jinnan District Tianjin 300350 P. R. China
| | - Bo Su
- State Key Laboratory of Medical Chemical Biology, College of Pharmacy, Nankai University 38 Tongyan Road, Jinnan District Tianjin 300350 P. R. China
| |
Collapse
|
15
|
Guillet SG, Logvinov AA, Voloshkin VA, Martynova EA, Nolan SP. Access to Azetidines via Gold Mediated Energy Transfer Photocatalysis. Org Lett 2023; 25:1403-1408. [PMID: 36847204 DOI: 10.1021/acs.orglett.3c00136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/01/2023]
Abstract
The area of energy transfer photocatalysis to generate four-membered rings is experiencing an unprecedented level of activity. Here, we report an operationally simple method toward azetidines from 2-isoxasoline-3-carboxylates and alkenes, using [Au(cbz)(NHC)] complexes as photocatalysts. The procedure enables the reaction for a wide range of substrates. Mechanistic studies confirm the energy transfer pathway. This contribution adds to the earlier reported use of these gold catalysts as a potentially versatile tool in energy transfer chemistry and catalysis.
Collapse
Affiliation(s)
- Sébastien G Guillet
- Department of Chemistry and Centre for Sustainable Chemistry, Ghent University, Campus Sterre, Building S-3, Krijgslaan 281, 9000 Ghent, Belgium
| | - Aleksei A Logvinov
- Department of Chemistry and Centre for Sustainable Chemistry, Ghent University, Campus Sterre, Building S-3, Krijgslaan 281, 9000 Ghent, Belgium
| | - Vladislav A Voloshkin
- Department of Chemistry and Centre for Sustainable Chemistry, Ghent University, Campus Sterre, Building S-3, Krijgslaan 281, 9000 Ghent, Belgium
| | - Ekaterina A Martynova
- Department of Chemistry and Centre for Sustainable Chemistry, Ghent University, Campus Sterre, Building S-3, Krijgslaan 281, 9000 Ghent, Belgium
| | - Steven P Nolan
- Department of Chemistry and Centre for Sustainable Chemistry, Ghent University, Campus Sterre, Building S-3, Krijgslaan 281, 9000 Ghent, Belgium
| |
Collapse
|
16
|
McDonald TR, Rousseaux SAL. Synthesis of 3-borylated cyclobutanols from epihalohydrins or epoxy alcohol derivatives. Chem Sci 2023; 14:963-969. [PMID: 36755731 PMCID: PMC9890513 DOI: 10.1039/d2sc06088d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Accepted: 12/20/2022] [Indexed: 12/24/2022] Open
Abstract
There is an increasing interest in cyclobutanes within the medicinal chemistry community. Therefore, methods to prepare cyclobutanes that contain synthetic handles for further elaboration are of interest. Herein, we report a new approach for the synthesis of 3-borylated cyclobutanols via a formal [3 + 1]-cycloaddition using readily accessible 1,1-diborylalkanes and epihalohydrins or epoxy alcohol derivatives. 1-Substituted epibromohydrin starting materials provide access to borylated cyclobutanols containing substituents at three of the four positions on the cyclobutane core, and enantioenriched epibromohydrins lead to enantioenriched cyclobutanols with high levels of enantiospecificity (>98%). Finally, derivatization studies demonstrate the synthetic utility of both the OH and Bpin handles.
Collapse
Affiliation(s)
- Tyler R. McDonald
- Department of Chemistry, University of Toronto. 80 St. George StreetTorontoONCanada
| | | |
Collapse
|