1
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Koike T, Yu JK, Hansmann MM. Ph 3PCN 2: A stable reagent for carbon-atom transfer. Science 2024; 385:305-311. [PMID: 39024456 DOI: 10.1126/science.ado4564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Revised: 04/18/2024] [Accepted: 06/03/2024] [Indexed: 07/20/2024]
Abstract
Precise modification of a chemical site in a molecule at the single-atom level is one of the most elegant yet difficult transformations in chemistry. A reagent specifically designed for chemoselective introduction of monoatomic carbon is a particularly formidable challenge. Here, we report a straightforward, azide-free synthesis of a crystalline and isolable diazophosphorus ylide, Ph3PCN2, a stable compound with a carbon atom bonded to two chemically labile groups, triphenylphosphine (PPh3) and dinitrogen (N2). Without any additives, the diazophosphorus ylide serves as a highly selective transfer reagent for fragments, including Ph3PC, to deliver phosphorus ylide-terminated heterocumulenes and CN2 to produce multisubstituted pyrazoles. Ultimately, even exclusive carbon-atom transfer is possible. In reactions with aldehydes and acyclic and cyclic ketones (R2C=O), the carbon-atom substitution forms a vinylidene (R2C=C:) en route to alkynes or butatrienes.
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Affiliation(s)
- Taichi Koike
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, 44227 Dortmund, Germany
| | - Jhen-Kuei Yu
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, 44227 Dortmund, Germany
| | - Max M Hansmann
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, 44227 Dortmund, Germany
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2
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Chen L, Ji H, Ding Y, Szostak M, Liu C. Palladium-Catalyzed Decarbonylative Sonogashira Alkynylation of Carboxylic-Phosphoric Anhydrides. J Org Chem 2024; 89:2665-2674. [PMID: 38288991 DOI: 10.1021/acs.joc.3c02701] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2024]
Abstract
We report the first palladium-catalyzed decarbonylative alkynylation of carboxylic-phosphoric anhydrides via highly selective C(O)-O bond cleavage. Carboxylic-phosphoric anhydrides are highly active carboxylic acid derivatives, which are generated through activating carboxylic acids using phosphates by esterification or direct dehydrogenative coupling with phosphites. Highly valuable internal alkynes have been generated by the present method, and the efficiency of this approach has been demonstrated through a wide substrate scope and excellent functional group tolerance.
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Affiliation(s)
- Lan Chen
- Department of Chemistry, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - Haiyao Ji
- Department of Chemistry, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - Yimin Ding
- Department of Chemistry, Shanghai University, 99 Shangda Road, Shanghai 200444, China
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Chengwei Liu
- Department of Chemistry, Shanghai University, 99 Shangda Road, Shanghai 200444, China
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3
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Das E, Feliciano MAM, Yamanushkin P, Lin X, Gold B. Oxa-azabenzobenzocyclooctynes (O-ABCs): heterobiarylcyclooctynes bearing an endocyclic heteroatom. Org Biomol Chem 2023; 21:8857-8862. [PMID: 37881858 DOI: 10.1039/d3ob01559a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2023]
Abstract
We report the synthesis of heterobiarylcyclooctynes bearing an endocyclic heteroatom, oxa-azabenzobenzocyclooctynes (O-ABCs). The integration of design strategies for accelerating strain-promoted azide-alkyne cycloadditions results in reactivity with organic azides that surpasses all cyclooctyne reagents reported to date. O-ABCs and related compounds provide insights into the effects of structural modifications on reactivity that can aid in the design of new reagents for click and bioorthogonal chemistry.
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Affiliation(s)
- Eshani Das
- Department of Chemistry and Chemical Biology, University of New Mexico, New Mexico, 87131, USA
| | - Mark Aldren M Feliciano
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico, 88003, USA.
- Department of Chemistry and Chemical Biology, University of New Mexico, New Mexico, 87131, USA
| | - Pavel Yamanushkin
- Department of Chemistry and Chemical Biology, University of New Mexico, New Mexico, 87131, USA
| | - Xinsong Lin
- Department of Chemistry and Biochemistry Florida State University, Tallahassee, FL, 32306, USA
| | - Brian Gold
- Department of Chemistry and Biochemistry, New Mexico State University, Las Cruces, New Mexico, 88003, USA.
- Department of Chemistry and Chemical Biology, University of New Mexico, New Mexico, 87131, USA
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4
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Guo FK, Lu YL, Huang MY, Yang JM, Guo JL, Wan ZY, Zhu SF. Wittig/B─H insertion reaction: A unique access to trisubstituted Z-alkenes. SCIENCE ADVANCES 2023; 9:eadj2486. [PMID: 37703379 PMCID: PMC10499320 DOI: 10.1126/sciadv.adj2486] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Accepted: 08/11/2023] [Indexed: 09/15/2023]
Abstract
The Wittig reaction, which is one of the most effective methods for synthesizing alkenes from carbonyl compounds, generally gives thermodynamically stable E-alkenes, and synthesis of trisubstituted Z-alkenes from ketones presents notable challenges. Here, we report what we refer to as Wittig/B─H insertion reactions, which innovatively combine a Wittig reaction with carbene insertion into a B─H bond and constitute a promising method for the synthesis of thermodynamically unstable trisubstituted Z-boryl alkenes. Combined with the easy transformations of boryl group, this methodology provides efficient access to a variety of previously unavailable trisubstituted Z-alkenes and thus provides a platform for discovery of pharmaceuticals. The unique Z-selectivity of the reaction is determined by the maximum overlap of the orbitals between the B─H bond of the borane adduct and the alkylidene carbene intermediate in the transition state.
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Affiliation(s)
- Feng-Kai Guo
- Frontiers Science Center for New Organic Matter, the State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Yi-Lin Lu
- Frontiers Science Center for New Organic Matter, the State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Ming-Yao Huang
- Frontiers Science Center for New Organic Matter, the State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Ji-Min Yang
- Frontiers Science Center for New Organic Matter, the State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Jia-Lei Guo
- Frontiers Science Center for New Organic Matter, the State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
| | - Zi-Yi Wan
- Frontiers Science Center for New Organic Matter, the State Key Laboratory and Institute of Elemento-Organic Chemistry, College of Chemistry, Nankai University, Tianjin 300071, China
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5
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Hansmann MM. Diazoalkenes: From an Elusive Intermediate to a Stable Substance Class in Organic Chemistry. Angew Chem Int Ed Engl 2023; 62:e202304574. [PMID: 37095063 DOI: 10.1002/anie.202304574] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 04/22/2023] [Accepted: 04/24/2023] [Indexed: 04/26/2023]
Abstract
Over decades diazoalkenes (R2 C=C=N2 ) were postulated as reactive intermediates in organic chemistry even though their direct spectroscopic detection proved very challenging. In the 1970/80ies several groups probed their existence mainly indirectly by trapping experiments or directly by matrix-isolation studies. In 2021, our group and the Severin group reported independently the synthesis and characterization of the first room-temperature stable diazoalkenes, which initiated a rapidly expanding research field. Up to now four different classes of N-heterocyclic substituted room-temperature stable diazoalkenes have been reported. Their properties and unique reactivity, such as N2 /CO exchange or utilization as vinylidene precursors in organic and transition metal chemistry are presented. This review summarizes the early discoveries of diazoalkenes from their initial postulation as transient, elusive species up to the recent findings of the room-temperature stable derivatives.
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Affiliation(s)
- Max M Hansmann
- Technische Universität Dortmund, Fakultät für Chemie und Chemische Biologie, Otto-Hahn-Str. 6, Dortmund, Germany
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6
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Ye M, Hou M, Wang Y, Ma X, Yang K, Song Q. Arylation of Terminal Alkynes: Transition-Metal-Free Sonogashira-Type Coupling for the Construction of C(sp)-C(sp 2) Bonds. Org Lett 2023; 25:1787-1792. [PMID: 36884031 DOI: 10.1021/acs.orglett.3c00586] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
Abstract
Alkynes are attractive synthons for organic chemistry. Despite the prevalence of transition-metal-catalyzed Sonogashira reactions, a transition-metal-free version of the arylation of terminal alkynes is elusive. Herein, we report an efficient transition-metal-free Sonogashira-type coupling reaction for the one-pot arylation of alkynes to construct C(sp)-C(sp2) bonds from a tetracoordinate boron intermediate with NIS as a mediator. With its high efficiency, wide substrate range, and good functional group tolerance, this method is further supported by the gram-scale synthesis and subsequent modification of complex molecules.
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Affiliation(s)
- Mingxing Ye
- Key Laboratory of Molecule Synthesis and Function Discovery, College of Chemistry at Fuzhou University, Fujian Province University, Fuzhou, Fujian 350108, P. R. China
| | - Mengyuan Hou
- Key Laboratory of Molecule Synthesis and Function Discovery, College of Chemistry at Fuzhou University, Fujian Province University, Fuzhou, Fujian 350108, P. R. China
| | - Yahao Wang
- Key Laboratory of Molecule Synthesis and Function Discovery, College of Chemistry at Fuzhou University, Fujian Province University, Fuzhou, Fujian 350108, P. R. China
| | - Xingxing Ma
- Key Laboratory of Molecule Synthesis and Function Discovery, College of Chemistry at Fuzhou University, Fujian Province University, Fuzhou, Fujian 350108, P. R. China
| | - Kai Yang
- Key Laboratory of Molecule Synthesis and Function Discovery, College of Chemistry at Fuzhou University, Fujian Province University, Fuzhou, Fujian 350108, P. R. China
| | - Qiuling Song
- Key Laboratory of Molecule Synthesis and Function Discovery, College of Chemistry at Fuzhou University, Fujian Province University, Fuzhou, Fujian 350108, P. R. China.,School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, P. R. China
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7
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Anderson TE, Thamattoor DM, Phillips DL. Formation of 3-Oxa- and 3-Thiacyclohexyne from Ring Expansion of Heterocyclic Alkylidene Carbenes: A Mechanistic Study. Org Lett 2023; 25:1364-1369. [PMID: 36856659 PMCID: PMC10012261 DOI: 10.1021/acs.orglett.3c00042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
The rearrangement pathways of two alkylidene carbenes appended to an oxa or thiacyclopentane into the corresponding heterocyclohexynes were elucidated using 13C-labeling experiments. Both carbenes exhibited a preference for migration of the allylic carbon bound to the heteroatom. Anomeric interactions involving a heteroatom lone pair and antibonding orbital of the migrating bond and inductive destabilization of the minor migratory pathway are discussed as plausible reasons for the observed trends.
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Affiliation(s)
- T E Anderson
- Department of Chemistry, Colby College, 5765 Mayflower Hill, Waterville, Maine 04901, USA
| | - Dasan M Thamattoor
- Department of Chemistry, Colby College, 5765 Mayflower Hill, Waterville, Maine 04901, USA
| | - David Lee Phillips
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Pok Fu Lam 999077, Hong Kong S.A.R
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8
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Barrows RD, Dresel MJ, Emge TJ, Rablen PR, Knapp S. Stereoelectronic Features of a Complex Ketene Dimerization Reaction. Molecules 2021; 27:molecules27010066. [PMID: 35011298 PMCID: PMC8746406 DOI: 10.3390/molecules27010066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2021] [Revised: 12/14/2021] [Accepted: 12/21/2021] [Indexed: 11/22/2022] Open
Abstract
The amidation reaction of a tetrahydroisoquinolin-1-one-4-carboxylic acid is a key step in the multi-kilogram-scale preparation of the antimalarial drug SJ733, now in phase 2 clinical trials. In the course of investigating THIQ carboxamidations, we found that propanephosphonic acid anhydride (T3P) is an effective reagent, although the yield and byproducts vary with the nature and quantity of the base. As a control, the T3P reaction of a 3-(2-thienyl) THIQ was performed in the absence of the amine, and the products were characterized: among them are three dimeric allenes and two dimeric lactones. A nucleophile-promoted ketene dimerization process subject to subtle steric and stereoelectronic effects accounts for their formation. Two novel monomeric products, a decarboxylated isoquinolone and a purple, fused aryl ketone, were also isolated, and mechanisms for their formation from the ketene intermediate are proposed.
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Affiliation(s)
- Robert D. Barrows
- Department of Chemistry and Chemical Biology, Rutgers—The State University of New Jersey, 123 Bevier Road, Piscataway, NJ 08854, USA; (R.D.B.); (M.J.D.); (T.J.E.)
| | - Mark J. Dresel
- Department of Chemistry and Chemical Biology, Rutgers—The State University of New Jersey, 123 Bevier Road, Piscataway, NJ 08854, USA; (R.D.B.); (M.J.D.); (T.J.E.)
| | - Thomas J. Emge
- Department of Chemistry and Chemical Biology, Rutgers—The State University of New Jersey, 123 Bevier Road, Piscataway, NJ 08854, USA; (R.D.B.); (M.J.D.); (T.J.E.)
| | - Paul R. Rablen
- Department of Chemistry and Biochemistry, Swarthmore College, 500 College Avenue, Swarthmore, PA 19081, USA;
| | - Spencer Knapp
- Department of Chemistry and Chemical Biology, Rutgers—The State University of New Jersey, 123 Bevier Road, Piscataway, NJ 08854, USA; (R.D.B.); (M.J.D.); (T.J.E.)
- Correspondence: ; Tel.: +1-848-445-2627
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9
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Antoni PW, Reitz J, Hansmann MM. N 2/CO Exchange at a Vinylidene Carbon Center: Stable Alkylidene Ketenes and Alkylidene Thioketenes from 1,2,3-Triazole Derived Diazoalkenes. J Am Chem Soc 2021; 143:12878-12885. [PMID: 34348463 DOI: 10.1021/jacs.1c06906] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
We present a new class of room-temperature stable diazoalkenes featuring a 1,2,3-triazole backbone. Dinitrogen of the diazoalkene moiety can be thermally displaced by an isocyanide and carbon monoxide. The latter alkylidene ketenes are typically considered as highly reactive compounds, traditionally only accessible by flash vacuum pyrolysis. We present a new and mild synthetic approach to the first structurally characterized alkylidene ketenes by a substitution reaction. Density functional theory calculations suggest the substitution with isocyanides to take place via a stepwise addition/elimination mechanism. In the case of carbon monoxide, the reaction proceeds through an unusual concerted exchange at a vinylidene carbon center. The vinylidene ketenes react with carbon disulfide via a four-membered thiete intermediate to give vinylidene thioketenes under release of COS. We present spectroscopic as well as structural data for the complete isoelectronic series (R2C═C═X; X = N2, CO, CNR, CS) including 1J(13C-13C) data. As N2, CO, and isocyanides belong to the archetypical ligands in transition-metal chemistry, this process can be interpreted in analogy to coordination chemistry as a ligand exchange reaction at a vinylidene carbon center.
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Affiliation(s)
- Patrick W Antoni
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227 Dortmund, Germany
| | - Justus Reitz
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227 Dortmund, Germany
| | - Max M Hansmann
- Fakultät für Chemie und Chemische Biologie, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44227 Dortmund, Germany
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10
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Dones JM, Abularrage NS, Khanal N, Gold B, Raines RT. Acceleration of 1,3-Dipolar Cycloadditions by Integration of Strain and Electronic Tuning. J Am Chem Soc 2021; 143:9489-9497. [PMID: 34151576 DOI: 10.1021/jacs.1c03133] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The 1,3-dipolar cycloaddition between azides and alkynes provides new means to probe and control biological processes. A major challenge is to achieve high reaction rates with stable reagents. The optimization of alkynyl reagents has relied on two strategies: increasing strain and tuning electronics. We report on the integration of these strategies. A computational analysis suggested that a CH → N aryl substitution in dibenzocyclooctyne (DIBO) could be beneficial. In transition states, the nitrogen of 2-azabenzo-benzocyclooctyne (ABC) engages in an n→π* interaction with the C=O of α-azidoacetamides and forms a hydrogen bond with the N-H of α-diazoacetamides. These dipole-specific interactions act cooperatively with electronic activation of the strained π-bond to increase reactivity. We found that ABC does indeed react more quickly with α-azidoacetamides and α-diazoacetamides than its constitutional isomer, dibenzoazacyclooctyne (DIBAC). ABC and DIBAC have comparable chemical stability in a biomimetic solution. Both ABC and DIBO are accessible in three steps by the alkylidene carbene-mediated ring expansion of commercial cycloheptanones. Our findings enhance the accessibility and utility of 1,3-dipolar cycloadditions and encourage further innovation.
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Affiliation(s)
- Jesús M Dones
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Nile S Abularrage
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Namrata Khanal
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Brian Gold
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.,Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| | - Ronald T Raines
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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11
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Kimura T, Sekiguchi K, Ando A, Imafuji A. Fritsch-Buttenberg-Wiechell rearrangement of magnesium alkylidene carbenoids leading to the formation of alkynes. Beilstein J Org Chem 2021; 17:1352-1359. [PMID: 34136014 PMCID: PMC8182682 DOI: 10.3762/bjoc.17.94] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 05/18/2021] [Indexed: 11/23/2022] Open
Abstract
A series of 1-heteroatom-substituted vinyl p-tolyl sulfoxides were prepared and treated with organometallic reagents to evaluate which combination of sulfoxides and organometallic reagents yielded alkynes the most efficiently. The use of 1-chlorovinyl p-tolyl sulfoxide and isopropylmagnesium chloride was optimal for this purpose. A variety of 1-chlorovinyl p-tolyl sulfoxides were prepared from carbonyl compounds and chloromethyl p-tolyl sulfoxide and were converted into alkynes via the sulfoxide/magnesium exchange reaction and subsequent Fritsch–Buttenberg–Wiechell (FBW) rearrangement of the resulting magnesium alkylidene carbenoids. The mechanism of the FBW rearrangement of magnesium alkylidene carbenoids was studied by using 13C-labeled sulfoxides and by using DFT calculations.
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Affiliation(s)
- Tsutomu Kimura
- Department of Chemistry, Graduate School of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Koto Sekiguchi
- Department of Chemistry, Graduate School of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Akane Ando
- Department of Chemistry, Graduate School of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
| | - Aki Imafuji
- Department of Chemistry, Graduate School of Science, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan
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12
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Wei R, Hall AMR, Behrens R, Pritchard MS, King EJ, Lloyd‐Jones GC. Stopped‐Flow
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F NMR Spectroscopic Analysis of a Protodeboronation Proceeding at the Sub‐Second Time‐Scale. European J Org Chem 2021. [DOI: 10.1002/ejoc.202100290] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Ran Wei
- School of Chemistry The University of Edinburgh Joseph Black Building David Brewster Road Edinburgh EH9 3FJ UK
| | - Andrew M. R. Hall
- School of Chemistry The University of Edinburgh Joseph Black Building David Brewster Road Edinburgh EH9 3FJ UK
| | - Richard Behrens
- Laboratory of Engineering Thermodynamics (LTD) Technische Universität Kaiserslautern Erwin-Schrödinger-Straße 44 Kaiserslautern 67663 Germany
| | | | - Edward J. King
- TgK Scientific Ltd. Bradford on Avon Wiltshire BA15 1DH UK
| | - Guy C. Lloyd‐Jones
- School of Chemistry The University of Edinburgh Joseph Black Building David Brewster Road Edinburgh EH9 3FJ UK
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