1
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Chen L, Zhou W, Zhang J, Ding Y, Szostak M, Liu C. Deoxygenative alkynylation of amides via CO bond cleavage. Chem Commun (Camb) 2024. [PMID: 39037708 DOI: 10.1039/d4cc02316a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/23/2024]
Abstract
A novel deoxygenative alkynylation of amides promoted by a synergistic action of a divalent rare-earth element and a transition metal has been developed. In this method, α-alkynyl substituted amines are synthesized from unactivated amides and alkynes in a single transformation. Broad substrate scope and excellent selectivity for CO cleavage has been demonstrated. This approach represents a general method for the construction of versatile α-alkynyl substituted amines from unactivated amide bonds.
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Affiliation(s)
- Lan Chen
- Department of Chemistry, Shanghai University, 99 Shangda Road, Shanghai 200444, China.
| | - Wei Zhou
- Department of Chemistry, Shanghai University, 99 Shangda Road, Shanghai 200444, China.
| | - Jianwen Zhang
- 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, NJ 07102, USA.
| | - Chengwei Liu
- Department of Chemistry, Shanghai University, 99 Shangda Road, Shanghai 200444, China.
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2
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Zheng JY, Luo Y, Ou TT, Zhang XJ, Lao YQ, Feng N, Peng JB, Zhang XZ, Yao X, Ma AJ. Acid-Promoted Cyclization of α-Azidobenzyl Ketones through C═N Bond Formation: Synthesis of 6-Substituted Quinoline Derivatives. Org Lett 2024; 26:586-590. [PMID: 38198745 DOI: 10.1021/acs.orglett.3c03697] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2024]
Abstract
An acid-promoted cyclization of α-azidobenzyl ketones has been developed for the synthesis of 6-substituted quinoline derivatives. A variety of synthetically useful 6-OTf or -OMs quinoline derivatives were obtained in moderate to good yields. The reaction proceeds via C═N bond formation without organophosphine, providing convenient access to structurally interesting and synthetically important 6-substituted quinoline derivatives in moderate to good yields. A mechanistic perspective that is different from the traditional intramolecular Schmidt reaction has been proposed.
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Affiliation(s)
- Jing-Yun Zheng
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong 529020, China
| | - Ying Luo
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong 529020, China
| | - Ting-Ting Ou
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong 529020, China
| | - Xin-Jie Zhang
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong 529020, China
| | - Yong-Qiang Lao
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong 529020, China
| | - Na Feng
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong 529020, China
| | - Jin-Bao Peng
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong 529020, China
| | - Xiang-Zhi Zhang
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong 529020, China
| | - Xiaojun Yao
- Centre for Artificial Intelligence Driven Drug Discovery, Faculty of Applied Sciences, Macao Polytechnic University, Macao 999078, China
| | - Ai-Jun Ma
- School of Biotechnology and Health Sciences, Wuyi University, Jiangmen, Guangdong 529020, China
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3
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Yanai H, Terajima Y, Kleemiss F, Grabowsky S, Matsumoto T. Reversing the Bond Length Alternation Order in Conjugated Polyenes by Substituent Effects. Chemistry 2023; 29:e202203538. [PMID: 36515459 DOI: 10.1002/chem.202203538] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/14/2022] [Accepted: 12/14/2022] [Indexed: 12/15/2022]
Abstract
We have synthesised several push-pull substituted conjugated polyenes and determined their accurate C-C bond lengths and charge-density distributions by utilising quantum crystallographic techniques. In a series of alkene, dienes, and triene bearing two (trifluoromethyl)sulfonyl (triflyl) groups on the terminal carbon atom, unique reversal of the bond-length alternation (BLA) order has been observed. This is a pronounced aberration from the molecular structure predicted by the Lewis-structure-based neutral resonance structure. Such reversal of BLA order has not been observed in push-pull compounds bearing conventional electron-withdrawing groups such as carbonyl and cyano groups instead of triflyl groups. Bonding behaviour of both normal and reversed bond length alternating systems has been revealed by complementary bonding analysis using several bond descriptors based on the experimentally fitted wavefunctions.
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Affiliation(s)
- Hikaru Yanai
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
| | - Yoshihiko Terajima
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
| | - Florian Kleemiss
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland.,Faculty of Chemistry and Pharmacy, University of Regensburg, Universitätsstr. 31, D-93053, Regensburg, Germany
| | - Simon Grabowsky
- Department of Chemistry, Biochemistry and Pharmaceutical Sciences, University of Bern, Freiestrasse 3, CH-3012, Bern, Switzerland
| | - Takashi Matsumoto
- School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
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4
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Liu Z, Zhou Y, Yuan L. Hydrogen-bonded aromatic amide macrocycles: synthesis, properties and functions. Org Biomol Chem 2022; 20:9023-9051. [PMID: 36128982 DOI: 10.1039/d2ob01263d] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
As a classic example of nearly planar cyclic compounds, hydrogen-bonded aromatic amide (H-bonded aramide) macrocycles, consisting of consecutive intramolecular hydrogen bonds and aromatic residues, receive considerable research attention due to their rich host-guest chemistry. This review provides a detailed summary of the synthesis, properties and functions of H-bonded aramide macrocycles and their derivatives. Herein, the constitutional patterns of these macrocycles are divided into two subcategories: interior hydrogen bonding motifs and exterior hydrogen bonding motifs. Based on these two motifs, we summarize the facile synthesis, self-assembly, host-guest interaction complexation of H-bonded aramide macrocycles and the resulting applications such as molecular recognition, artificial ion channels, soft materials, supramolecular catalysis, and artificial molecular machines. The development of H-bonded aramide macrocycles is still in its infancy, although a considerable number of examples have been reported. We hope that this review will provide useful information and unlock new opportunities in this field.
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Affiliation(s)
- Zejiang Liu
- College of Chemistry, Key Laboratory of Radiation Physics and Technology of Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, China.
| | - Yidan Zhou
- College of Chemistry, Key Laboratory of Radiation Physics and Technology of Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, China.
| | - Lihua Yuan
- College of Chemistry, Key Laboratory of Radiation Physics and Technology of Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064, China.
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5
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Zhao Q, Li G, Nareddy P, Jordan F, Lalancette R, Szostak R, Szostak M. Structures of the Most Twisted Thioamide and Selenoamide: Effect of Higher Chalcogens of Twisted Amides on N-C(X) Resonance. Angew Chem Int Ed Engl 2022; 61:e202207346. [PMID: 35776856 PMCID: PMC9398953 DOI: 10.1002/anie.202207346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Indexed: 11/09/2022]
Abstract
Amide bond replacement with planar isosteric chalcogen analogues has an important implication for the properties of the N-C(X) linkage in structural chemistry, biochemistry and organic synthesis. Herein, we report the first higher chalcogen derivatives of non-planar twisted amides. The synthesis of twisted thioamide in a versatile system has been accomplished by direct thionation without cleavage of the σ N-C bond. The synthesis of twisted selenoamide has been accomplished by selenation with Woollins' reagent. The structures of higher chalcogen analogues of non-planar amides were unambiguously confirmed by X-ray crystallography. Reactivity studies were conducted to determine the effect of isologous N-C(O) to N-C(X) replacement on the properties of the amide linkage. Computational studies were employed to evaluate structural and energetic parameters of amide bond alteration in higher chalcogen amides. The study provides the first experimental evidence on the effect of chalcogen isologues on the structural and electronic properties of the non-planar amide N-C(X) linkage.
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Affiliation(s)
- Qun Zhao
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA
| | - Guangchen Li
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA
| | - Pradeep Nareddy
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA
| | - Frank Jordan
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA
| | - Roger Lalancette
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw, 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ 07102, USA
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6
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Szyszko B. Phenanthrene‐Embedded Carbaporphyrinoids and Related Systems: From Ligands to Cages and Molecular Switches. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200714] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Bartosz Szyszko
- University of Wroclaw: Uniwersytet Wroclawski Chemistry 14 F. Joliot-Curie 14 50383 Wroclaw POLAND
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7
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Zhao Q, Li G, Nareddy P, Jordan F, Lalancette R, Szostak R, Szostak M. Structures of the Most Twisted Thioamide and Selenoamide: Effect of Higher Chalcogens of Twisted Amides on N–C(X) Resonance. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202207346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Qun Zhao
- Rutgers University: Rutgers The State University of New Jersey Chemistry UNITED STATES
| | - Guangchen Li
- Rutgers University: Rutgers The State University of New Jersey Chemistry UNITED STATES
| | - Pradeep Nareddy
- Rutgers University: Rutgers The State University of New Jersey Chemistry UNITED STATES
| | - Frank Jordan
- Rutgers University System: Rutgers The State University of New Jersey Chemistry UNITED STATES
| | - Roger Lalancette
- Rutgers University System: Rutgers The State University of New Jersey Chemistry UNITED STATES
| | - Roman Szostak
- Uniwersytet Wroclawski Wydzial Chemii Chemistry UNITED STATES
| | - Michal Szostak
- Rutgers University Department of Chemistry 73 Warren St. 07102 Newark UNITED STATES
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8
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Wang CA, Rahman MM, Bisz E, Dziuk B, Szostak R, Szostak M. Palladium-NHC (NHC = N-heterocyclic Carbene)-Catalyzed Suzuki–Miyaura Cross-Coupling of Alkyl Amides. ACS Catal 2022. [DOI: 10.1021/acscatal.1c05738] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Chang-An Wang
- College of Chemistry and Chemical Engineering, Taishan University, Tai’an, Shandong 271000, People’s Republic of China
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Md. Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Błażej Dziuk
- Department of Chemistry, University of Science and Technology, Norwida 4/6 14, Wroclaw 50-373, Poland
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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9
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Abstract
In this contribution, we provide a comprehensive overview of acyclic twisted amides, covering the literature since 1993 (the year of the first recognized report on acyclic twisted amides) through June 2020. The review focuses on classes of acyclic twisted amides and their key structural properties, such as amide bond twist and nitrogen pyramidalization, which are primarily responsible for disrupting nN to π*C═O conjugation. Through discussing acyclic twisted amides in comparison with the classic bridged lactams and conformationally restricted cyclic fused amides, the reader is provided with an overview of amidic distortion that results in novel conformational features of acyclic amides that can be exploited in various fields of chemistry ranging from organic synthesis and polymers to biochemistry and structural chemistry and the current position of acyclic twisted amides in modern chemistry.
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Affiliation(s)
- Guangrong Meng
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Jin Zhang
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States.,College of Chemistry and Chemical Engineering, Key Laboratory of Chemical Additives for China National Light Industry, Shaanxi University of Science and Technology, Xi'an 710021, China
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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10
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Xu M, Paul MK, Bullard KK, DuPre C, Gutekunst WR. Modulating Twisted Amide Geometry and Reactivity Through Remote Substituent Effects. J Am Chem Soc 2021; 143:14657-14666. [PMID: 34463473 DOI: 10.1021/jacs.1c05854] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The unusual reactivity of twisted amides has long been associated with the degree of amide distortion, though classical bridged bicyclic amides offer limited methods to further modify these parameters. Here, we report that the geometry and reactivity of a single twisted amide scaffold can be significantly modulated through remote substituent effects. Guided by calculated ground state geometries, a library of twisted amide derivatives was efficiently prepared through a divergent synthetic strategy. Kinetic and mechanistic investigations of these amides in the alkylation/halide-rebound ring-opening reaction with alkyl halides show a strong positive correlation between the electron donating ability of the substituent and distortion of the amide bond, leading to rates of nucleophilic substitution spanning nearly 2 orders of magnitude. The rate limiting step of the cascade sequence is found to be dependent on the nature of the substituent, and additional studies highlight the role of solvent polarity and halide ion on reaction pathway and efficiency.
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11
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Ielo L, Pace V, Holzer W, Rahman MM, Meng G, Szostak R, Szostak M. Electrophilicity Scale of Activated Amides: 17 O NMR and 15 N NMR Chemical Shifts of Acyclic Twisted Amides in N-C(O) Cross-Coupling. Chemistry 2020; 26:16246-16250. [PMID: 32668046 DOI: 10.1002/chem.202003213] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2020] [Indexed: 12/17/2022]
Abstract
The structure and properties of amides are of tremendous interest in organic synthesis and biochemistry. Traditional amides are planar and the carbonyl group non-electrophilic due to nN →π*C=O conjugation. In this study, we report electrophilicity scale by exploiting 17 O NMR and 15 N NMR chemical shifts of acyclic twisted and destabilized acyclic amides that have recently received major attention as precursors in N-C(O) cross-coupling by selective oxidative addition as well as precursors in electrophilic activation of N-C(O) bonds. Most crucially, we demonstrate that acyclic twisted amides feature electrophilicity of the carbonyl group that ranges between that of acid anhydrides and acid chlorides. Furthermore, a wide range of electrophilic amides is possible with gradually varying carbonyl electrophilicity by steric and electronic tuning of amide bond properties. Overall, the study quantifies for the first time that steric and electronic destabilization of the amide bond in common acyclic amides renders the amide bond as electrophilic as acid anhydrides and chlorides. These findings should have major implications on the fundamental properties of amide bonds.
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Affiliation(s)
- Laura Ielo
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, Vienna, 1090, Austria
| | - Vittorio Pace
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, Vienna, 1090, Austria.,Department of Chemistry, University of Torino, Via P. Giuria 7, Torino, 10125, Italy
| | - Wolfgang Holzer
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, Vienna, 1090, Austria
| | - Md Mahbubur Rahman
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ, 07102, United States
| | - Guangrong Meng
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ, 07102, United States
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw, 50383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, NJ, 07102, United States
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12
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Ohwada T, Otani Y. Lactam Amide Spinning. J SYN ORG CHEM JPN 2020. [DOI: 10.5059/yukigoseikyokaishi.78.1006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Tomohiko Ohwada
- Graduate School of Pharmaceutical Sciences, The University of Tokyo
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13
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Lambert KM, Cox JB, Liu L, Jackson AC, Yruegas S, Wiberg KB, Wood JL. Total Synthesis of (±)‐Phyllantidine: Development and Mechanistic Evaluation of a Ring Expansion for Installation of Embedded Nitrogen‐Oxygen Bonds. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202003829] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
- Kyle M. Lambert
- Department of Chemistry and Biochemistry Baylor University One Bear Place 97348 Waco TX 76798 USA
| | - Joshua B. Cox
- Department of Chemistry and Biochemistry Baylor University One Bear Place 97348 Waco TX 76798 USA
| | - Lin Liu
- Department of Chemistry and Biochemistry Baylor University One Bear Place 97348 Waco TX 76798 USA
| | - Amy C. Jackson
- Department of Chemistry and Biochemistry Baylor University One Bear Place 97348 Waco TX 76798 USA
| | - Sam Yruegas
- Department of Chemistry and Biochemistry Baylor University One Bear Place 97348 Waco TX 76798 USA
| | - Kenneth B. Wiberg
- Department of Chemistry Yale University New Haven CT 06520 USA
- 865 Central Avenue Needham MA 02492 USA
| | - John L. Wood
- Department of Chemistry and Biochemistry Baylor University One Bear Place 97348 Waco TX 76798 USA
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14
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Lambert KM, Cox JB, Liu L, Jackson AC, Yruegas S, Wiberg KB, Wood JL. Total Synthesis of (±)-Phyllantidine: Development and Mechanistic Evaluation of a Ring Expansion for Installation of Embedded Nitrogen-Oxygen Bonds. Angew Chem Int Ed Engl 2020; 59:9757-9766. [PMID: 32271982 DOI: 10.1002/anie.202003829] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 04/05/2020] [Indexed: 11/06/2022]
Abstract
The development of a concise total synthesis of (±)-phyllantidine (1), a member of the securinega family of alkaloids containing an unusual oxazabicyclo[3.3.1]nonane core, is described. The synthesis employs a unique synthetic strategy featuring the ring expansion of a substituted cyclopentanone to a cyclic hydroxamic acid as a key step that allows facile installation of the embedded nitrogen-oxygen (N-O) bond. The optimization of this sequence to effect the desired regiochemical outcome and its mechanistic underpinnings were assessed both computationally and experimentally. This synthetic approach also features an early-stage diastereoselective aldol reaction to assemble the substituted cyclopentanone, a mild reduction of an amide intermediate without N-O bond cleavage, and the rapid assembly of the butenolide found in (1) via use of the Bestmann ylide.
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Affiliation(s)
- Kyle M Lambert
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place 97348, Waco, TX, 76798, USA
| | - Joshua B Cox
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place 97348, Waco, TX, 76798, USA
| | - Lin Liu
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place 97348, Waco, TX, 76798, USA
| | - Amy C Jackson
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place 97348, Waco, TX, 76798, USA
| | - Sam Yruegas
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place 97348, Waco, TX, 76798, USA
| | - Kenneth B Wiberg
- Department of Chemistry, Yale University, New Haven, CT, 06520, USA.,865 Central Avenue, Needham, MA, 02492, USA
| | - John L Wood
- Department of Chemistry and Biochemistry, Baylor University, One Bear Place 97348, Waco, TX, 76798, USA
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15
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Takezawa H, Shitozawa K, Fujita M. Enhanced reactivity of twisted amides inside a molecular cage. Nat Chem 2020; 12:574-578. [PMID: 32313238 DOI: 10.1038/s41557-020-0455-y] [Citation(s) in RCA: 140] [Impact Index Per Article: 35.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 03/09/2020] [Indexed: 11/09/2022]
Abstract
When an amide group is distorted from its planar conformation, the conjugation between the nitrogen lone pair and the π* orbital of the carbonyl is disrupted and the reactivity towards nucleophiles is enhanced. Although there are several reports on the synthesis of activated twisted amides, amide activation through mechanical twisting is much less common. Here, we report twisted amides that are stabilized through their inclusion in a self-assembled coordination cage. When secondary aromatic amides are included in a Td-symmetric cage, the cis-twisted conformation is favoured over the trans-planar one-as evidenced by single-crystal X-ray diffraction analysis-revealing that the amide can twist by up to 34°. As a consequence of this distortion, the hydrolysis of amides is significantly accelerated upon inclusion.
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Affiliation(s)
- Hiroki Takezawa
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
| | - Kosuke Shitozawa
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo, Japan
| | - Makoto Fujita
- Department of Applied Chemistry, School of Engineering, The University of Tokyo, Bunkyo-ku, Tokyo, Japan. .,Division of Advanced Molecular Science, Institute for Molecular Science (IMS), Okazaki, Aichi, Japan.
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16
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Zhao Q, Lalancette R, Szostak R, Szostak M. Ring-Opening Olefin Metathesis of Twisted Amides: Activation of Amide Bonds by C═C Cleavage. ACS Catal 2019. [DOI: 10.1021/acscatal.9b04033] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Qun Zhao
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Roger Lalancette
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- College of Chemistry and Chemical Engineering and Key Laboratory of Auxiliary Chemistry and Technology for Chemical Industry, Ministry of Education, Shaanxi University of Science and Technology, Xi’an 710021, China
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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17
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Xu M, Bullard KK, Nicely AM, Gutekunst WR. Resonance promoted ring-opening metathesis polymerization of twisted amides. Chem Sci 2019; 10:9729-9734. [PMID: 32055341 PMCID: PMC6993617 DOI: 10.1039/c9sc03602d] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Accepted: 08/30/2019] [Indexed: 12/31/2022] Open
Abstract
The living ring-opening metathesis polymerization (ROMP) of an unsaturated twisted amide using the third-generation Grubbs initiator is described. Unlike prior examples of ROMP monomers that rely on angular or steric strain for propagation, this system is driven by resonance destabilization of the amide that arises from geometric constraints of the bicyclic framework. Upon ring-opening, the amide can rotate and rehybridize to give a stabilized and planar conjugated system that promotes living propagation. The absence of other strain elements in the twisted amide is supported by the inability of a carbon analogue of the monomer to polymerize and computational studies that find resonance destabilization accounts for 11.3 kcal mol-1 of the overall 12.0 kcal mol-1 ring strain. The twisted amide polymerization is capable of preparing high molecular weight polymers rapidly at room temperature, and post-polymerization modification combined with 2D NMR spectroscopy confirms a regioirregular polymer microstructure.
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Affiliation(s)
- Mizhi Xu
- School of Chemistry and Biochemistry , Georgia Institute of Technology , 901 Atlantic Drive NW , Atlanta , Georgia 30332 , USA .
| | - Krista K Bullard
- School of Chemistry and Biochemistry , Georgia Institute of Technology , 901 Atlantic Drive NW , Atlanta , Georgia 30332 , USA .
| | - Aja M Nicely
- School of Chemistry and Biochemistry , Georgia Institute of Technology , 901 Atlantic Drive NW , Atlanta , Georgia 30332 , USA .
| | - Will R Gutekunst
- School of Chemistry and Biochemistry , Georgia Institute of Technology , 901 Atlantic Drive NW , Atlanta , Georgia 30332 , USA .
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18
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19
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Harris T, Alabugin IV. Strain and stereoelectronics in cycloalkyne click chemistry. MENDELEEV COMMUNICATIONS 2019. [DOI: 10.1016/j.mencom.2019.05.001] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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20
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Pace V, Holzer W, Ielo L, Shi S, Meng G, Hanna M, Szostak R, Szostak M. 17O NMR and 15N NMR chemical shifts of sterically-hindered amides: ground-state destabilization in amide electrophilicity. Chem Commun (Camb) 2019; 55:4423-4426. [PMID: 30916689 DOI: 10.1039/c9cc01402k] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The structure and spectroscopic properties of the amide bond are a topic of fundamental interest in chemistry and biology. Herein, we report 17O NMR and 15N NMR spectroscopic data for four series of sterically-hindered acyclic amides. Despite the utility of 17O NMR and 15N NMR spectroscopy, these methods are severely underutilized in the experimental determination of electronic properties of the amide bond. The data demonstrate that a combined use of 17O NMR and 15N NMR serves as a powerful tool in assessing electronic effects of the amide bond substitution as a measure of electrophilicity of the amide bond. Notably, we demonstrate that steric destabilization of the amide bond results in electronically-activated amides that are comparable in terms of electrophilicity to acyl fluorides and carboxylic acid anhydrides.
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Affiliation(s)
- Vittorio Pace
- Department of Pharmaceutical Chemistry, Faculty of Life Sciences, University of Vienna, Althanstrasse 14, Vienna A-1090, Austria.
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21
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Fu L, Xu M, Yu J, Gutekunst WR. Halide-Rebound Polymerization of Twisted Amides. J Am Chem Soc 2019; 141:2906-2910. [DOI: 10.1021/jacs.8b13731] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Affiliation(s)
- Liangbing Fu
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive NW, Atlanta, Georgia 30332, United States
| | - Mizhi Xu
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive NW, Atlanta, Georgia 30332, United States
| | - Jiyao Yu
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive NW, Atlanta, Georgia 30332, United States
| | - Will R. Gutekunst
- School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive NW, Atlanta, Georgia 30332, United States
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22
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Amide nitrogen pyramidalization changes lactam amide spinning. Nat Commun 2019; 10:461. [PMID: 30692534 PMCID: PMC6349922 DOI: 10.1038/s41467-018-08249-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 12/19/2018] [Indexed: 11/29/2022] Open
Abstract
Although cis-trans lactam amide rotation is fundamentally important, it has been little studied, except for a report on peptide-based lactams. Here, we find a consistent relationship between the lactam amide cis/trans ratios and the rotation rates between the trans and cis lactam amides upon the lactam chain length of the stapling side-chain of two 7-azabicyclo[2.2.1]heptane bicyclic units, linked through a non-planar amide bond. That is, as the chain length increased, the rotational rate of trans to cis lactam amide was decreased, and consequently the trans ratio was increased. This chain length-dependency of the lactam amide isomerization and our simulation studies support the idea that the present lactam amides can spin through 360 degrees as in open-chain amides, due to the occurrence of nitrogen pyramidalization. The tilting direction of the pyramidal amide nitrogen atom of the bicyclic systems is synchronized with the direction of the semicircle-rotation of the amide. Cis-trans lactam amide rotation is a fundamental process and its understanding might aid molecular design. Here, the authors report the synthesis and study of bicyclic lactams which undergo spin through 360 degrees as in open-chain amides, due to the occurrence of nitrogen pyramidalization.
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23
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Kupietz K, Białek MJ, Białońska A, Szyszko B, Latos-Grażyński L. Organocopper(III) Phenanthriporphyrin-Exocyclic Transformations. Inorg Chem 2019; 58:1451-1461. [PMID: 30600994 DOI: 10.1021/acs.inorgchem.8b02997] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
5,6-Dimethoxyphenanthriporphyrin 1 and 5,6-dioxophenanthriporphyrin 2 act as suitable organometallic ligands for copper(III), adopting trianionic [CCNN] coordination cores. Under oxidizing conditions, in the presence of methanol, copper(III) phenanthriporphyrin 1-Cu undergoes transformation to copper(III) phenanthriporphodimethene with methoxy substituents attached to two trans meso positions. Addition of acids to 1-Cu yields two isomeric copper(III) isophenanthriporphyrins protonated on one of the meso carbon atoms. Protonation of copper(III) 5,6-dioxophenanthriporphyrin 2-Cu yields the aromatic diprotonated complex 2-Cu-H22+. In the presence of HBF4 2-Cu undergoes borylation at the carbonyl oxygen atoms, forming an aromatic exocyclic boron(III) complex.
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Affiliation(s)
- Kamil Kupietz
- Department of Chemistry , University of Wrocław , F. Joliot-Curie 14 , 50-383 Wrocław , Poland
| | - Michał J Białek
- Department of Chemistry , University of Wrocław , F. Joliot-Curie 14 , 50-383 Wrocław , Poland
| | - Agata Białońska
- Department of Chemistry , University of Wrocław , F. Joliot-Curie 14 , 50-383 Wrocław , Poland
| | - Bartosz Szyszko
- Department of Chemistry , University of Wrocław , F. Joliot-Curie 14 , 50-383 Wrocław , Poland
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24
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Szostak R, Szostak M. Tröger's Base Twisted Amides: High Amide Bond Twist and N-/O-Protonation Aptitude. J Org Chem 2019; 84:1510-1516. [PMID: 30571109 DOI: 10.1021/acs.joc.8b02937] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Tröger's base twisted amides have emerged as attractive scaffolds to readily achieve substantial nonplanarity of the amide bond in a bicyclic lactam framework. Herein, we report structures and proton affinities of a diverse set of Tröger's base twisted amides and compare them with related nonplanar bridged lactams. The data demonstrate that Tröger's base twisted amides embedded in a [3.3.1] scaffold are among the most twisted bridged lactams prepared to date. Intriguingly, while these amides also favor N-protonation, our data show that the best model for probing N-protonation aptitude in the series of nonplanar amides are less twisted benzofused 1-azabicyclo[3.3.1]nonan-2-one derivatives. This work (1) provides the understanding for future design of nonplanar bridged lactams to directly access N-protonated amide bonds, (2) validates the use of the additive Winkler-Dunitz distortion parameter, and (3) emphasizes the importance of peripheral modification to modulate properties of nonplanar amides.
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Affiliation(s)
- Roman Szostak
- Department of Chemistry , Wroclaw University , F. Joliot-Curie 14 , Wroclaw 50-383 , Poland
| | - Michal Szostak
- Department of Chemistry , Rutgers University , 73 Warren Street , Newark , New Jersey 07102 , United States
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25
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Chemistry of Bridged Lactams: Recent Developments. Molecules 2019; 24:molecules24020274. [PMID: 30642094 PMCID: PMC6359620 DOI: 10.3390/molecules24020274] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 01/09/2019] [Accepted: 01/10/2019] [Indexed: 12/15/2022] Open
Abstract
Bridged lactams represent the most effective and wide-ranging method of constraining the amide bond in a non-planar conformation. A previous comprehensive review on this topic was published in 2013 (Chem. Rev.2013, 113, 5701–5765). In the present review, which is published as a part of the Special Issue on Amide Bond Activation, we present an overview of the recent developments in the field of bridged lactams that have taken place in the last five years and present a critical assessment of the current status of bridged lactams in synthetic and physical organic chemistry. This review covers the period from 2014 until the end of 2018 and is intended as an update to Chem. Rev.2013, 113, 5701–5765. In addition to bridged lactams, the review covers recent advances in the chemistry of bridged sultams, bridged enamines and related non-planar structures.
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26
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Liu C, Shi S, Liu Y, Liu R, Lalancette R, Szostak R, Szostak M. The Most Twisted Acyclic Amides: Structures and Reactivity. Org Lett 2018; 20:7771-7774. [DOI: 10.1021/acs.orglett.8b03175] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Chengwei Liu
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Shicheng Shi
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Yongmei Liu
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
- College of Chemistry and Chemical Engineering, Yangzhou University, 180 Siwangting Road, Yangzhou 225002, China
| | - Ruzhang Liu
- College of Chemistry and Chemical Engineering, Yangzhou University, 180 Siwangting Road, Yangzhou 225002, China
| | - Roger Lalancette
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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27
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Szostak R, Liu C, Lalancette R, Szostak M. Twisted N-Acyl-hydantoins: Rotationally Inverted Urea-Imides of Relevance in N-C(O) Cross-coupling. J Org Chem 2018; 83:14676-14682. [PMID: 30352152 DOI: 10.1021/acs.joc.8b02691] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
We report a combined structural and computational study on the properties of twisted acyclic hydantoins. These compounds feature cyclic urea-imide moiety that is widely found in bioactive compounds and is structurally related to the classic bridged hydantoins proposed by Smissman more than 50 years ago. We demonstrate that C to N-substitution of the imide moiety in the succinimide ring to give hydantoin results in one of the most distorted acyclic amide bonds reported to date. The energetic properties of twisted acyclic hydantoins with respect to structures, resonance energies, barriers to rotation, and proton affinities are discussed. The energetic and structural properties of twisted acyclic hydantoins described provide a benchmark to facilitate the development of twisted amides based on the biorelevant cyclic urea-imide scaffold.
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Affiliation(s)
- Roman Szostak
- Department of Chemistry , Wroclaw University , F. Joliot-Curie 14 , Wroclaw 50-383 , Poland
| | - Chengwei Liu
- Department of Chemistry , Rutgers University , 73 Warren Street , Newark , New Jersey 07102 , United States
| | - Roger Lalancette
- Department of Chemistry , Rutgers University , 73 Warren Street , Newark , New Jersey 07102 , United States
| | - Michal Szostak
- Department of Chemistry , Rutgers University , 73 Warren Street , Newark , New Jersey 07102 , United States
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28
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Amatov T, Jangra H, Pohl R, Cisařová I, Zipse H, Jahn U. Unique Stereoselective Homolytic C-O Bond Activation in Diketopiperazine-Derived Alkoxyamines by Adjacent Amide Pyramidalization. Chemistry 2018; 24:15336-15345. [PMID: 30092124 DOI: 10.1002/chem.201803284] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Revised: 08/02/2018] [Indexed: 12/12/2022]
Abstract
Simple monocyclic diketopiperazine (DKP)-derived alkoxyamines exhibit unprecedented activation of a remote C-O bond for homolysis by amide distortion. The combination of strain-release-driven amide planarization and the persistent radical effect (PRE) enables a unique, irreversible, and quantitative trans→cis isomerization under much milder conditions than typically observed for such homolysis-limited reactions. This isomerization is shown to be general and independent of the steric and electronic nature of both the amino acid side chains and the substituents at the DKP nitrogen atoms. Homolysis rate constants are determined, and they significantly differ for both the labile trans diastereomers and the stable cis diastereomers. To reveal the factors influencing this unusual process, structural features of the kinetic trans diastereomers and thermodynamic cis diastereomers are investigated in the solid state and in solution. X-ray crystallographic analysis and computational studies indicate substantial distortion of the amide bond from planarity in the trans-alkoxyamines, and this is believed to be the cause for the facile and quantitative isomerization. Thus, these amino-acid-derived alkoxyamines are the first examples that exhibit a large thermodynamic preference for one diastereomer over the other upon thermal homolysis, and this allows controlled switching of configurations and configurational cycling.
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Affiliation(s)
- Tynchtyk Amatov
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 16610, Prague, Czech Republic.,Ludwig Maximilian University, Department of Chemistry, Butenandstrasse 5-13, 81377, München, Germany
| | - Harish Jangra
- Ludwig Maximilian University, Department of Chemistry, Butenandstrasse 5-13, 81377, München, Germany
| | - Radek Pohl
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 16610, Prague, Czech Republic
| | - Ivana Cisařová
- Department of Inorganic Chemistry, Faculty of Science, Charles University in Prague, Hlavova 2030/8, 12843, Prague, Czech Republic
| | - Hendrik Zipse
- Ludwig Maximilian University, Department of Chemistry, Butenandstrasse 5-13, 81377, München, Germany
| | - Ullrich Jahn
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 16610, Prague, Czech Republic
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29
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Urushibara K, Ferrand Y, Liu Z, Masu H, Pophristic V, Tanatani A, Huc I. Frustrierte Helizität: Zusammenführung divergierender Enden einer stabilen aromatischen Amid‐Helix zu einem fluxionalen Makrocyclus. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201802159] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Ko Urushibara
- Department of Chemistry Faculty of Science Ochanomizu University 2-1-1 Otsuka, Bunkyo-ku Tokyo 112-8610 Japan
- CBMN (UMR5248) Univ. Bordeaux – CNRS – IPB Institut Européen de Chimie et Biologie 2 rue Escarpit 33600 Pessac Frankreich
| | - Yann Ferrand
- CBMN (UMR5248) Univ. Bordeaux – CNRS – IPB Institut Européen de Chimie et Biologie 2 rue Escarpit 33600 Pessac Frankreich
| | - Zhiwei Liu
- Department of Chemistry &Biochemistry University of the Sciences 600 South 43rd Street Philadelphia PA 19104 USA
| | - Hyuma Masu
- Center for Analytical Instrumentation Chiba University 1-33 Yayoi, Inage Chiba 263-8522 Japan
| | - Vojislava Pophristic
- Department of Chemistry &Biochemistry University of the Sciences 600 South 43rd Street Philadelphia PA 19104 USA
| | - Aya Tanatani
- Department of Chemistry Faculty of Science Ochanomizu University 2-1-1 Otsuka, Bunkyo-ku Tokyo 112-8610 Japan
| | - Ivan Huc
- CBMN (UMR5248) Univ. Bordeaux – CNRS – IPB Institut Européen de Chimie et Biologie 2 rue Escarpit 33600 Pessac Frankreich
- Department Pharmazie Ludwig-Maximilians-Universität Butenandtstraße 5–13 81377 München Deutschland
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30
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Yu H, Hu B, Huang H. Nickel-Catalyzed Alkylarylation of Activated Alkenes with Benzyl-amines via C-N Bond Activation. Chemistry 2018. [PMID: 29517114 DOI: 10.1002/chem.201800543] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
A nickel-catalyzed alkylarylation of active alkenes with tertiary benzylamines was achieved by charge-transfer-complex promoted C-N bond activation. The reaction proceeded through initial Ni-catalyzed C-N bond activation, followed by sequential radical addition, redox and proton abstraction with cleaved amine moiety in the absence of oxidant, and provides an efficient method to prepare various alkyl-substituted oxindoles and dihydroquinolinones in good yields.
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Affiliation(s)
- Hui Yu
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000, P.R. China.,University of Chinese Academy of Sciences, Beijing, 100049, P.R. China
| | - Bin Hu
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000, P.R. China
| | - Hanmin Huang
- State Key Laboratory for Oxo Synthesis and Selective Oxidation, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000, P.R. China.,Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemistry, Center for Excellence in Molecular Synthesis, University of Science and Technology of China, Chinese Academy of Sciences, Hefei, 230026, P.R. China
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31
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Urushibara K, Ferrand Y, Liu Z, Masu H, Pophristic V, Tanatani A, Huc I. Frustrated Helicity: Joining the Diverging Ends of a Stable Aromatic Amide Helix to Form a Fluxional Macrocycle. Angew Chem Int Ed Engl 2018; 57:7888-7892. [DOI: 10.1002/anie.201802159] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Indexed: 11/06/2022]
Affiliation(s)
- Ko Urushibara
- Department of Chemistry Faculty of Science Ochanomizu University 2-1-1 Otsuka, Bunkyo-ku Tokyo 112-8610 Japan
- CBMN (UMR5248), Univ. Bordeaux—CNRS—IPB Institut Européen de Chimie et Biologie 2 rue Escarpit 33600 Pessac France
| | - Yann Ferrand
- CBMN (UMR5248), Univ. Bordeaux—CNRS—IPB Institut Européen de Chimie et Biologie 2 rue Escarpit 33600 Pessac France
| | - Zhiwei Liu
- Department of Chemistry &Biochemistry University of the Sciences 600 South 43rd Street Philadelphia PA 19104 USA
| | - Hyuma Masu
- Center for Analytical Instrumentation Chiba University 1–33 Yayoi, Inage Chiba 263-8522 Japan
| | - Vojislava Pophristic
- Department of Chemistry &Biochemistry University of the Sciences 600 South 43rd Street Philadelphia PA 19104 USA
| | - Aya Tanatani
- Department of Chemistry Faculty of Science Ochanomizu University 2-1-1 Otsuka, Bunkyo-ku Tokyo 112-8610 Japan
| | - Ivan Huc
- CBMN (UMR5248), Univ. Bordeaux—CNRS—IPB Institut Européen de Chimie et Biologie 2 rue Escarpit 33600 Pessac France
- Department Pharmazie Ludwig-Maximilians-Universität Butenandtstr. 5–13 81377 München Germany
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32
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Meng G, Szostak M. N
‐Acyl‐Glutarimides: Privileged Scaffolds in Amide N–C Bond Cross‐Coupling. European J Org Chem 2018. [DOI: 10.1002/ejoc.201800109] [Citation(s) in RCA: 108] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Guangrong Meng
- Department of Chemistry Rutgers University 73 Warren Street 07102 Newark NJ United States
| | - Michal Szostak
- Department of Chemistry Rutgers University 73 Warren Street 07102 Newark NJ United States
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33
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Adachi S, Kumagai N, Shibasaki M. Conquering amide planarity: Structural distortion and its hidden reactivity. Tetrahedron Lett 2018. [DOI: 10.1016/j.tetlet.2018.01.097] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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34
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Bisz E, Piontek A, Dziuk B, Szostak R, Szostak M. Barriers to Rotation in ortho-Substituted Tertiary Aromatic Amides: Effect of Chloro-Substitution on Resonance and Distortion. J Org Chem 2018; 83:3159-3163. [DOI: 10.1021/acs.joc.8b00019] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Elwira Bisz
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Aleksandara Piontek
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Błażej Dziuk
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
| | - Roman Szostak
- Department of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Opole University, 48 Oleska Street, Opole 45-052, Poland
- Department of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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35
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Abstract
Amide rotation of peptidyl-prolyl fragments is an important factor in backbone structure organization of proteins. Computational studies have indicated that this rotation preferentially proceeds through a defined transition-state structure (syn/exo). Here, we complement the computational findings by determining the amide bond rotation barriers for derivatives of the two symmetric proline analogues, meso and racemic pyrrolidine-2,5-dicarboxylic acids. The rotations around these residues represent syn/exo-syn/exo and anti/endo-syn/exo hybrid transition states for the meso and racemic diastereomer, respectively. The rotation barriers are lower for the former rotation by about 9 kJ mol-1 (aqueous medium), suggesting a strong preference for the syn/exo (clockwise) rotation over the anti/endo (anticlockwise) rotation. The results show that both hybrid rotation processes are enthalpically driven but respond differently to solvent polarity changes due to the different transition state dipole-dipole interactions.
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Affiliation(s)
- Vladimir Kubyshkin
- Biocatalysis Group, Institute of Chemistry, Technical University of Berlin, Müller-Breslau-Str. 10, Berlin 10623, Germany.
| | - Nediljko Budisa
- Biocatalysis Group, Institute of Chemistry, Technical University of Berlin, Müller-Breslau-Str. 10, Berlin 10623, Germany.
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36
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Meng G, Shi S, Lalancette R, Szostak R, Szostak M. Reversible Twisting of Primary Amides via Ground State N-C(O) Destabilization: Highly Twisted Rotationally Inverted Acyclic Amides. J Am Chem Soc 2018; 140:727-734. [PMID: 29240413 DOI: 10.1021/jacs.7b11309] [Citation(s) in RCA: 141] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Since the seminal studies by Pauling in 1930s, planarity has become the defining characteristic of the amide bond. Planarity of amides has central implications for the reactivity and chemical properties of amides of relevance to a range of chemical disciplines. While the vast majority of amides are planar, nonplanarity has a profound effect on the properties of the amide bond, with the most common method to restrict the amide bond relying on the incorporation of the amide function into a rigid cyclic ring system. In a major departure from this concept, here, we report the first class of acyclic twisted amides that can be prepared, reversibly, from common primary amides in a single, operationally trivial step. Di-tert-butoxycarbonylation of the amide nitrogen atom yields twisted amides in which the amide bond exhibits nearly perpendicular twist. Full structural characterization of a range of electronically diverse compounds from this new class of twisted amides is reported. Through reactivity studies we demonstrate unusual properties of the amide bond, wherein selective cleavage of the amide bond can be achieved by a judicious choice of the reaction conditions. Through computational studies we evaluate structural and energetic details pertaining to the amide bond deformation. The ability to selectively twist common primary amides, in a reversible manner, has important implications for the design and application of the amide bond nonplanarity in structural chemistry, biochemistry and organic synthesis.
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Affiliation(s)
- Guangrong Meng
- Department of Chemistry, Rutgers University , 73 Warren Street, Newark, New Jersey 07102, United States
| | - Shicheng Shi
- Department of Chemistry, Rutgers University , 73 Warren Street, Newark, New Jersey 07102, United States
| | - Roger Lalancette
- Department of Chemistry, Rutgers University , 73 Warren Street, Newark, New Jersey 07102, United States
| | - Roman Szostak
- Department of Chemistry, Wroclaw University , F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Michal Szostak
- Department of Chemistry, Rutgers University , 73 Warren Street, Newark, New Jersey 07102, United States
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37
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Kupietz K, Białek MJ, Białońska A, Szyszko B, Latos-Grażyński L. Aromaticity control via modifications of a macrocyclic frame: 5,6-dimethoxyphenanthriporphyrin and 5,6-dioxophenanthriporphyrin. Org Chem Front 2018. [DOI: 10.1039/c8qo00751a] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Antiaromatic phenanthriporphyrin and nonaromatic 5,6-dioxophenanthriporphyrin reveal specific reactivity toward protic and Lewis acids yielding respectively nonaromatic and aromatic macrocycles.
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38
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Liniger M, Liu Y, Stoltz BM. Sequential Ruthenium Catalysis for Olefin Isomerization and Oxidation: Application to the Synthesis of Unusual Amino Acids. J Am Chem Soc 2017; 139:13944-13949. [PMID: 28918631 PMCID: PMC5628162 DOI: 10.1021/jacs.7b08496] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
How can you use a ruthenium isomerization catalyst twice? A ruthenium-catalyzed sequence for the formal two-carbon scission of allyl groups to carboxylic acids has been developed. The reaction includes an initial isomerization step using commercially available ruthenium catalysts followed by in situ transformation of the complex to a metal-oxo species, which is capable of catalyzing subsequent oxidation reactions. The method enables enantioselective syntheses of challenging α-tri- and tetrasubstituted α-amino acids including an expedient total synthesis of the antiepileptic drug levetiracetam.
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Affiliation(s)
| | - Yiyang Liu
- Warren and Katherine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Brian M. Stoltz
- Warren and Katherine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
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39
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Harris T, Gomes GDP, Ayad S, Clark RJ, Lobodin VV, Tuscan M, Hanson K, Alabugin IV. Twisted Cycloalkynes and Remote Activation of “Click” Reactivity. Chem 2017. [DOI: 10.1016/j.chempr.2017.07.011] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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40
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Pritchett BP, Donckele EJ, Stoltz BM. Enantioselective Catalysis Coupled with Stereodivergent Cyclization Strategies Enables Rapid Syntheses of (+)-Limaspermidine and (+)-Kopsihainanine A. Angew Chem Int Ed Engl 2017; 56:12624-12627. [PMID: 28872739 DOI: 10.1002/anie.201707304] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Indexed: 01/09/2023]
Abstract
Enantioselective Pd-catalyzed allylic alkylations of dihydropyrido[1,2-a]indolone (DHPI) substrates were used to construct the C20-quaternary stereocenters of multiple monoterpene indole alkaloids. Stereodivergent Pictet-Spengler and Bischler-Napieralski cyclization/reduction cascades furnish the cis- and trans-fused azadecalin subunits present in Aspidosperma and Kopsia alkaloids, respectively, en route to highly efficient syntheses of (+)-limaspermidine and (+)-kopsihainanine A.
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Affiliation(s)
- Beau P Pritchett
- Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd. MC 101-20, Pasadena, CA, 91125, USA
| | - Etienne J Donckele
- Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd. MC 101-20, Pasadena, CA, 91125, USA
| | - Brian M Stoltz
- Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering, Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 E. California Blvd. MC 101-20, Pasadena, CA, 91125, USA
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41
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Pritchett BP, Donckele EJ, Stoltz BM. Enantioselective Catalysis Coupled with Stereodivergent Cyclization Strategies Enables Rapid Syntheses of (+)‐Limaspermidine and (+)‐Kopsihainanine A. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201707304] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- Beau P. Pritchett
- Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering Division of Chemistry and Chemical Engineering California Institute of Technology 1200 E. California Blvd. MC 101-20 Pasadena CA 91125 USA
| | - Etienne J. Donckele
- Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering Division of Chemistry and Chemical Engineering California Institute of Technology 1200 E. California Blvd. MC 101-20 Pasadena CA 91125 USA
| | - Brian M. Stoltz
- Warren and Katharine Schlinger Laboratory for Chemistry and Chemical Engineering Division of Chemistry and Chemical Engineering California Institute of Technology 1200 E. California Blvd. MC 101-20 Pasadena CA 91125 USA
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42
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Szostak R, Meng G, Szostak M. Resonance Destabilization in N-Acylanilines (Anilides): Electronically-Activated Planar Amides of Relevance in N–C(O) Cross-Coupling. J Org Chem 2017; 82:6373-6378. [DOI: 10.1021/acs.joc.7b00971] [Citation(s) in RCA: 72] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Roman Szostak
- Department
of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Guangrong Meng
- Department
of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Michal Szostak
- Department
of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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43
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Hu F, Nareddy P, Lalancette R, Jordan F, Szostak M. σ N-C Bond Difunctionalization in Bridged Twisted Amides: Sew-and-Cut Activation Approach to Functionalized Isoquinolines. Org Lett 2017; 19:2386-2389. [PMID: 28437089 DOI: 10.1021/acs.orglett.7b00913] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
A rare example of highly selective σ N-C bond difunctionalization in bridged twisted lactams through N-C cleavage has been achieved. In combination with the intramolecular Heck cyclization, this method affords a two-step bond reorganization event ("sew-and-cut") to access functionalized isoquinoline ring systems directly with high atom economy. C-H bond functionalizations directed by a weakly coordinating bridged amide bond increase scaffold diversity. Preliminary mechanistic studies on the effect of amide distortion and the role of electrophile in this unusual σ N-C amide difunctionalization are described.
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Affiliation(s)
- Feng Hu
- Department of Chemistry, Rutgers University , 73 Warren Street, Newark, New Jersey 07102, United States
| | - Pradeep Nareddy
- Department of Chemistry, Rutgers University , 73 Warren Street, Newark, New Jersey 07102, United States
| | - Roger Lalancette
- Department of Chemistry, Rutgers University , 73 Warren Street, Newark, New Jersey 07102, United States
| | - Frank Jordan
- Department of Chemistry, Rutgers University , 73 Warren Street, Newark, New Jersey 07102, United States
| | - Michal Szostak
- Department of Chemistry, Rutgers University , 73 Warren Street, Newark, New Jersey 07102, United States
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44
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Liu C, Szostak M. Twisted Amides: From Obscurity to Broadly Useful Transition-Metal-Catalyzed Reactions by N−C Amide Bond Activation. Chemistry 2017; 23:7157-7173. [DOI: 10.1002/chem.201605012] [Citation(s) in RCA: 246] [Impact Index Per Article: 35.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2016] [Indexed: 02/05/2023]
Affiliation(s)
- Chengwei Liu
- Department of Chemistry; Rutgers University; 73 Warren Street Newark NJ 07102 USA
| | - Michal Szostak
- Department of Chemistry; Rutgers University; 73 Warren Street Newark NJ 07102 USA
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45
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Vatsadze SZ, Loginova YD, dos Passos Gomes G, Alabugin IV. Stereoelectronic Chameleons: The Donor–Acceptor Dichotomy of Functional Groups. Chemistry 2016; 23:3225-3245. [DOI: 10.1002/chem.201603491] [Citation(s) in RCA: 73] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Indexed: 01/28/2023]
Affiliation(s)
- Sergey Z. Vatsadze
- Department of Organic Chemistry, Faculty of Chemistry Lomonosov Moscow State University Leninsky gory, 1, 3 Moscow Russia
| | - Yulia D. Loginova
- Department of Organic Chemistry, Faculty of Chemistry Lomonosov Moscow State University Leninsky gory, 1, 3 Moscow Russia
| | - Gabriel dos Passos Gomes
- Department of Chemistry and Biochemistry Florida State University 95 Chieftan Way Tallahassee USA
| | - Igor V. Alabugin
- Department of Chemistry and Biochemistry Florida State University 95 Chieftan Way Tallahassee USA
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46
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Adachi S, Kumagai N, Shibasaki M. Pyramidalization/twisting of the amide functional group via remote steric congestion triggered by metal coordination. Chem Sci 2016; 8:85-90. [PMID: 28451151 PMCID: PMC5304688 DOI: 10.1039/c6sc03669d] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2016] [Accepted: 09/21/2016] [Indexed: 12/17/2022] Open
Abstract
The distortion of the planar structure of amides is manifested by taking advantage of the temporary increase of the peripheral steric factor.
For decades, the planarity of the amide functional group has garnered sustained interest in organic chemistry, enticing chemists to deform its usually characteristic high-fidelity plane. As opposed to the construction of amides that are distorted by imposing rigid covalent bond assemblies, we demonstrate herein the deformation of the amide plane through increased steric bulk in the periphery of the amide moiety, which is induced by coordination to metal cations. A crystallographic analysis revealed that the thus obtained amides exhibit significant pyramidalization and twisting upon coordination to the metals, while the amide functional group remained intact. The observed deformation, which should be attributed to through-space interactions, substantially enhanced the solvolytic cleavage of the amide, providing compelling evidence that temporary crowding in the periphery of the amide functional group may be used to control the reactivity of amides.
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Affiliation(s)
- Shinya Adachi
- Institute of Microbial Chemistry (BIKAKEN) , 3-14-23 Kamiosaki , Shinagawa-ku , Tokyo 141-0021 , Japan . ;
| | - Naoya Kumagai
- Institute of Microbial Chemistry (BIKAKEN) , 3-14-23 Kamiosaki , Shinagawa-ku , Tokyo 141-0021 , Japan . ;
| | - Masakatsu Shibasaki
- Institute of Microbial Chemistry (BIKAKEN) , 3-14-23 Kamiosaki , Shinagawa-ku , Tokyo 141-0021 , Japan . ;
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47
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Pace V, Holzer W, Meng G, Shi S, Lalancette R, Szostak R, Szostak M. Structures of Highly Twisted Amides Relevant to Amide N−C Cross-Coupling: Evidence for Ground-State Amide Destabilization. Chemistry 2016; 22:14494-8. [DOI: 10.1002/chem.201603543] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Indexed: 12/18/2022]
Affiliation(s)
- Vittorio Pace
- Department of Pharmaceutical Chemistry; Faculty of Life Sciences; University of Vienna; Althanstrasse 14 Vienna 1090 Austria
| | - Wolfgang Holzer
- Department of Pharmaceutical Chemistry; Faculty of Life Sciences; University of Vienna; Althanstrasse 14 Vienna 1090 Austria
| | - Guangrong Meng
- Department of Chemistry; Rutgers University; 73 Warren Street Newark NJ 07102 United States
| | - Shicheng Shi
- Department of Chemistry; Rutgers University; 73 Warren Street Newark NJ 07102 United States
| | - Roger Lalancette
- Department of Chemistry; Rutgers University; 73 Warren Street Newark NJ 07102 United States
| | - Roman Szostak
- Department of Chemistry; Wroclaw University; F. Joliot-Curie 14 Wroclaw 50-383 Poland
| | - Michal Szostak
- Department of Chemistry; Rutgers University; 73 Warren Street Newark NJ 07102 United States
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48
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Szostak R, Shi S, Meng G, Lalancette R, Szostak M. Ground-State Distortion in N-Acyl-tert-butyl-carbamates (Boc) and N-Acyl-tosylamides (Ts): Twisted Amides of Relevance to Amide N–C Cross-Coupling. J Org Chem 2016; 81:8091-4. [DOI: 10.1021/acs.joc.6b01560] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Affiliation(s)
- Roman Szostak
- Department
of Chemistry, Wroclaw University, F. Joliot-Curie 14, Wroclaw 50-383, Poland
| | - Shicheng Shi
- Department
of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Guangrong Meng
- Department
of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Roger Lalancette
- Department
of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
| | - Michal Szostak
- Department
of Chemistry, Rutgers University, 73 Warren Street, Newark, New Jersey 07102, United States
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49
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Pandey KK. Does hydrohalic acid HX (X = F, Cl) form true N-protonated twisted amide salts? Effects of anions on the ion-pair interactions and on the amide moiety in N-protonated tricyclic twisted amide salts. NEW J CHEM 2016. [DOI: 10.1039/c6nj01342b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The [BF4]− and [RSO3]− anions interact with N-protonated amide cations through N–H⋯F and N–H⋯O strong hydrogen bonds and hydrohalic acids form very weak N⋯H–X hydrogen bonds.
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Affiliation(s)
- Krishna K. Pandey
- School of Chemical Sciences
- Devi Ahilya University Indore
- Indore-452017
- India
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50
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Liu Y, Meng G, Liu R, Szostak M. Sterically-controlled intermolecular Friedel–Crafts acylation with twisted amides via selective N–C cleavage under mild conditions. Chem Commun (Camb) 2016; 52:6841-4. [DOI: 10.1039/c6cc02324j] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Highly chemoselective Friedel–Crafts acylation of arenes with twisted amides by N–C bond cleavage is reported for the first time.
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Affiliation(s)
- Yongmei Liu
- Department of Chemistry
- Rutgers University
- Newark
- USA
- College of Chemistry and Chemical Engineering
| | | | - Ruzhang Liu
- College of Chemistry and Chemical Engineering
- Yangzhou University
- Yangzhou 225002
- China
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