1
|
Liao H, Miñoza S, Lee S, Rueping M. Aza‐
Ortho
‐Quinone Methides as Reactive Intermediates: Generation and Utility in Contemporary Asymmetric Synthesis. Chemistry 2022; 28:e202201112. [DOI: 10.1002/chem.202201112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Indexed: 11/10/2022]
Affiliation(s)
- Hsuan‐Hung Liao
- Department of Chemistry National Sun Yat-sen University (NSYSU) 70 Lien-hai Rd. Kaohsiung 80424 Taiwan, (R.O.C
| | - Shinje Miñoza
- Department of Chemistry National Sun Yat-sen University (NSYSU) 70 Lien-hai Rd. Kaohsiung 80424 Taiwan, (R.O.C
| | - Shao‐Chi Lee
- KAUST Catalysis Center (KCC) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia
| | - Magnus Rueping
- KAUST Catalysis Center (KCC) King Abdullah University of Science and Technology (KAUST) Thuwal 23955-6900 Saudi Arabia
| |
Collapse
|
2
|
Yang F, Zhou X, Wei Y, Wang L, Jiang J. Hydroquinine-catalyzed asymmetric 1,4-hydrophosphination of in situ generated aza- o-quinone methides with H-phosphine oxides. Org Chem Front 2021. [DOI: 10.1039/d1qo00823d] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
An organocatalytic enantioselective 1,4-addition of H-phosphine oxides to in situ generated aza-o-quinone methides has been successfully established using hydroquinine.
Collapse
Affiliation(s)
- Fuxing Yang
- College of Chemistry and Chemical Engineering, Guangxi University, Nanning, 530004, P. R. China
| | - Xingcui Zhou
- College of Chemistry and Chemical Engineering, Guangxi University, Nanning, 530004, P. R. China
| | - Yongquan Wei
- College of Chemistry and Chemical Engineering, Guangxi University, Nanning, 530004, P. R. China
| | - Lisheng Wang
- College of Chemistry and Chemical Engineering, Guangxi University, Nanning, 530004, P. R. China
- Medical College, Guangxi University, Nanning, 530004, P. R. China
| | - Jun Jiang
- College of Chemistry and Chemical Engineering, Guangxi University, Nanning, 530004, P. R. China
- Guangxi Key Laboratory of Electrochemical Energy Materials, Nanning, Guangxi 530004, P. R. China
| |
Collapse
|
3
|
Salvio R, Placidi S, Bella M. Benzazetidines and Related Compounds: Synthesis and Potential. Chemistry 2020; 26:10157-10174. [DOI: 10.1002/chem.201905668] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Revised: 02/24/2020] [Indexed: 12/28/2022]
Affiliation(s)
- Riccardo Salvio
- Dipartimento di Scienze e Tecnologie Chimiche Università “Tor Vergata” Via della Ricerca Scientifica, 1 00133 Roma Italy
- ISB—CNR Sezione Meccanismi di Reazione Università La Sapienza 00185 Roma Italy
| | - Simone Placidi
- Dipartimento di Chimica Sapienza Università di Roma P.le Aldo Moro 5 00185 Roma Italy
| | - Marco Bella
- Dipartimento di Chimica Sapienza Università di Roma P.le Aldo Moro 5 00185 Roma Italy
| |
Collapse
|
4
|
Wu TH, Su ZS, Sung R, Sung K. Aza-ortho-Quinone Methide and Its Conjugated Acid: Reactivity, Stability and Acidity. Chemphyschem 2020; 21:307-312. [PMID: 31895487 DOI: 10.1002/cphc.201901133] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Revised: 12/26/2019] [Indexed: 11/08/2022]
Abstract
Aza-o-quinone methides and their conjugated acids are reactive drug metabolites that might react with nucleophilic sites of DNAs and proteins to cause cancer or immune responses, and their reactivity with water is the key information to judge if these metabolites are harmful in living systems. For the first time, aza-o-quinone methide (1) and its conjugated acid (2) are observed by laser flash photolysis, and their reactivity, stability and acidity in water are determined.
Collapse
Affiliation(s)
- Tun-Hui Wu
- Department of Chemistry, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Zih-Syuan Su
- Department of Chemistry, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Robert Sung
- Faculty of Family Medicine, Northern Ontario School of Medicine, Sudbury, P3E 2C6, Ontario, Canada
| | - Kuangsen Sung
- Department of Chemistry, National Cheng Kung University, Tainan, 70101, Taiwan
| |
Collapse
|
5
|
Škalamera Đ, Antol I, Mlinarić-Majerski K, Vančik H, Phillips DL, Ma J, Basarić N. Ultrafast Adiabatic Photodehydration of 2-Hydroxymethylphenol and the Formation of Quinone Methide. Chemistry 2018; 24:9426-9435. [PMID: 29677402 DOI: 10.1002/chem.201801543] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Indexed: 12/13/2022]
Abstract
The photochemical reactivity of 2-hydroxymethylphenol (1) was investigated experimentally by photochemistry under cryogenic conditions, by detecting reactive intermediates by IR spectroscopy, and by using nanosecond and femtosecond transient absorption spectroscopic methods in solution at room temperature. In addition, theoretical studies were performed to facilitate the interpretation of the experimental results and also to simulate the reaction pathway to obtain a better understanding of the reaction mechanism. The main finding of this work is that photodehydration of 1 takes place in an ultrafast adiabatic photochemical reaction without any clear intermediate, delivering quinone methide (QM) in the excited state. Upon photoexcitation to a higher vibrational level of the singlet excited state, 1 undergoes vibrational relaxation leading to two photochemical pathways, one by which synchronous elimination of H2 O gives QM 2 in its S1 state and the other by which homolytic cleavage of the phenolic O-H bond produces a phenoxyl radical (S0 ). Both are ultrafast processes that occur within a picosecond. The excited state of QM 2 (S1 ) probably deactivates to S0 through a conical intersection to give QM 2 (S0 ), which subsequently delivers benzoxete 4. Elucidation of the reaction mechanisms for the photodehydration of phenols by which QMs are formed is important to tune the reactivity of QMs with DNA and proteins for the potential application of QMs in medicine as therapeutic agents.
Collapse
Affiliation(s)
- Đani Škalamera
- Department of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10000, Zagreb, Croatia.,Department of Organic Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, 10000, Zagreb, Croatia
| | - Ivana Antol
- Department of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10000, Zagreb, Croatia
| | - Kata Mlinarić-Majerski
- Department of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10000, Zagreb, Croatia
| | - Hrvoj Vančik
- Department of Organic Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, 10000, Zagreb, Croatia
| | - David Lee Phillips
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., P.R. China
| | - Jiani Ma
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of, Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an, P.R. China
| | - Nikola Basarić
- Department of Organic Chemistry and Biochemistry, Ruđer Bošković Institute, Bijenička cesta 54, 10000, Zagreb, Croatia
| |
Collapse
|
6
|
Liao HH, Hsiao CC, Atodiresei I, Rueping M. Multiple Hydrogen-Bond Activation in Asymmetric Brønsted Acid Catalysis. Chemistry 2018; 24:7718-7723. [DOI: 10.1002/chem.201800677] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Indexed: 12/17/2022]
Affiliation(s)
- Hsuan-Hung Liao
- Institute of Organic Chemistry; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
| | - Chien-Chi Hsiao
- Institute of Organic Chemistry; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
| | - Iuliana Atodiresei
- Institute of Organic Chemistry; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
| | - Magnus Rueping
- Institute of Organic Chemistry; RWTH Aachen University; Landoltweg 1 52074 Aachen Germany
- King Abdullah University of Science and Technology (KAUST); KAUST Catalysis Center (KCC); Thuwal 23955-69 00 Saudi Arabia
| |
Collapse
|
7
|
Yang B, Gao S. Recent advances in the application of Diels–Alder reactions involving o-quinodimethanes, aza-o-quinone methides and o-quinone methides in natural product total synthesis. Chem Soc Rev 2018; 47:7926-7953. [DOI: 10.1039/c8cs00274f] [Citation(s) in RCA: 240] [Impact Index Per Article: 40.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This review summarizes recent advances in Diels–Alder reactions involving o-QDMs, o-QMs and aza-o-QMs. The power and potential of this strategy in organic synthesis and natural product total synthesis is highlighted.
Collapse
Affiliation(s)
- Baochao Yang
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200062
- China
| | - Shuanhu Gao
- Shanghai Key Laboratory of Green Chemistry and Chemical Processes
- School of Chemistry and Molecular Engineering
- East China Normal University
- Shanghai 200062
- China
| |
Collapse
|
8
|
Cao G, Wang Y, Cui T, Huang L, Teng D. Synthesis of 3,4,5-trisubstituted isoxazoles via 1,3-dipolar cycloaddition/SO2 extrusion of benzoisothiazole-2,2-dioxide-3-ylidenes with nitrile oxides. RSC Adv 2016. [DOI: 10.1039/c5ra26718h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
An straightforward synthesis of 3,4,5-trisubstituted isoxazole derivatives via 1,3-dipolar cycloaddtion/SO2 extrusion of benzoisothiazole-2,2-dioxide-3-ylidenes with nitrile oxides is reported using 4 Å molecular sieves as dehydrochlorinating agent.
Collapse
Affiliation(s)
- Guorui Cao
- College of Chemical Engineering
- Qingdao University of Science and Technology
- Qingdao 266042
- China
| | - Yu Wang
- College of Chemical Engineering
- Qingdao University of Science and Technology
- Qingdao 266042
- China
| | - Tao Cui
- College of Chemical Engineering
- Qingdao University of Science and Technology
- Qingdao 266042
- China
| | - Longjiang Huang
- College of Chemical Engineering
- Qingdao University of Science and Technology
- Qingdao 266042
- China
- State Key Laboratory of Bioactive Substance and Function of Natural Medicines
| | - Dawei Teng
- College of Chemical Engineering
- Qingdao University of Science and Technology
- Qingdao 266042
- China
| |
Collapse
|
9
|
Aromaticity and Conjugation in 1,2-Benzoquinone Valence Isomers and Congeners. ADVANCES IN HETEROCYCLIC CHEMISTRY 2014. [DOI: 10.1016/b978-0-12-800170-7.00003-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
|
10
|
Yang Z, Xu J. Synthesis of benzo-γ-sultams via the Rh-catalyzed aromatic C–H functionalization of diazosulfonamides. Chem Commun (Camb) 2014; 50:3616-8. [DOI: 10.1039/c4cc00250d] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Diazosulfonamides are first introduced and employed to synthesize 1-aryl-benzo-γ-sultams via Rh-catalyzed intramolecular aromatic C–H functionalization.
Collapse
Affiliation(s)
- Zhanhui Yang
- State Key Laboratory of Chemical Resource Engineering
- Department of Organic Chemistry
- Faculty of Science
- Beijing University of Chemical Technology
- Beijing 100029, P. R. China
| | - Jiaxi Xu
- State Key Laboratory of Chemical Resource Engineering
- Department of Organic Chemistry
- Faculty of Science
- Beijing University of Chemical Technology
- Beijing 100029, P. R. China
| |
Collapse
|
11
|
Meier H. Benzoxetes and benzothietes--heterocyclic analogues of benzocyclobutene. Molecules 2012; 17:1548-70. [PMID: 22314379 PMCID: PMC6268305 DOI: 10.3390/molecules17021548] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2011] [Revised: 01/13/2012] [Accepted: 01/17/2012] [Indexed: 11/16/2022] Open
Abstract
Benzo-condensed four-ring heterocycles, such as benzoxetes 1 and benzothietes 3 represent multi-purpose starting compounds for the preparation of various higher heterocyclic ring systems. The thermal or photochemical valence isomerizations between the benzenoid forms 1,3 and the higher reactive o-quinoid structures 2,4 provide the basis for the synthetic applications. On the other hand, this valence isomerization impedes in particular the generation and storage of 1 because the thermal equilibrium 1 ⇆ 2 is completely on the side of 2. Thus, the number of erroneous or questionable benzoxete structures published to date is surprisingly high. On the contrary, the thermal equilibrium 3 ⇆ 4 is on the side of the benzothietes 3, which makes them easily accessible, especially by different flash vacuum pyrolysis techniques. The present article gives a survey of the preparations of 1 and 2, and tries to stimulate their use in synthetic projects. Naphtho-condensed and higher condensed compounds and compounds with an exocyclic C=O or S=O double bond (lactones, thiolactones, sulfoxides and sulfones) are not covered in this article.
Collapse
Affiliation(s)
- Herbert Meier
- Institute of Organic Chemistry, University of Mainz, Duesbergweg 10-14, Mainz, Germany.
| |
Collapse
|
12
|
Ferreira SB, da Silva FDC, Pinto AC, Gonzaga DTG, Ferreira VF. Syntheses of chromenes and chromanesvia o-quinone methide intermediates. J Heterocycl Chem 2009. [DOI: 10.1002/jhet.232] [Citation(s) in RCA: 119] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
|
13
|
|
14
|
Chrobok A, Gössinger E, Kalb R, Orglmeister E, Schwaiger J. Towards EPC-syntheses of the structural class of cochleamycins and macquarimicins. Part 2: EPC-synthesis of the hydrindene subunit of the macquarimicins. Tetrahedron 2007. [DOI: 10.1016/j.tet.2007.05.094] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
15
|
Herzig Y, Lerman L, Goldenberg W, Lerner D, Gottlieb HE, Nudelman A. Hydroxy-1-aminoindans and derivatives: preparation, stability, and reactivity. J Org Chem 2007; 71:4130-40. [PMID: 16709052 DOI: 10.1021/jo052621m] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The chemical stability and reactivity of hydroxy-1-aminoindans and their N-propargyl derivatives are strongly affected by the position of the OH group and its orientation relative to that of the amino moiety. Thus, the 4- and 6-OH regioisomers were found to be stable, while the 5-OH analogues were found to be inherently unstable as the free bases. The latter, having a para orientation between the OH and the amino moieties, could be isolated only as their hydrochloride salts. 7-Hydroxy-1-aminoindans and 7-hydroxy-1-propargylaminoindans represent an intermediate case; while sufficiently stable even as free bases, they exhibit, under certain experimental conditions, unexpected reactivity. The instability of the 5- and 7-hydroxy-aminoindans is attributed to their facile conversion to the corresponding, reactive quinone methide (QM) intermediates. The o-QM obtained from 7-hydroxy-aminoindans was successfully trapped with ethyl vinyl ether via a Diels-Alder reaction to give tricyclic acetals 32a,b.
Collapse
Affiliation(s)
- Yaacov Herzig
- Global Innovative Research and Development, Teva Pharmaceutical Industries Limited, Netanya 42504, Israel
| | | | | | | | | | | |
Collapse
|
16
|
Modrzejewska H, Wojciechowski K. Synthesis and reactions of 3-alkylsulfanyl-1,3-dihydro-2,1-benzisothiazole 2,2-dioxides. Tetrahedron 2005. [DOI: 10.1016/j.tet.2005.07.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
17
|
Affiliation(s)
- Anil K Sadana
- Department of Chemistry, Rice University, Houston, Texas 77005-1892, USA
| | | | | |
Collapse
|
18
|
|
19
|
Amouri H, Le Bras J. Taming reactive phenol tautomers and o-quinone methides with transition metals: a structure-reactivity relationship. Acc Chem Res 2002; 35:501-10. [PMID: 12118989 DOI: 10.1021/ar010105m] [Citation(s) in RCA: 157] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Quinone methides act as important intermediates in organic syntheses, as well as in chemical and biological processes; however, examples of such isolated species are scarce as a result of their high reactivity. Phenol tautomers (keto form of phenol) are also important intermediates in several organic and organometallic reactions; nevertheless, isolated complexes are rare. This Account reviews the recent progress on the synthesis and reactivity of iridium and rhodium o-quinone methide complexes as well as on iridium-mediated ortho functionalization of phenols. This reaction was at the origin of the discovery of a general synthetic procedure to prepare the first metal-stabilized o-quinone methide.
Collapse
Affiliation(s)
- Hani Amouri
- Laboratoire de Chimie Inorganique et Matériaux, Moléculaires UMR 7071-CNRS, Université Pierre et Marie Curie, 4, place Jussieu, case 42, 75252 Paris Cedex 05, France.
| | | |
Collapse
|
20
|
Differentiation of planar chiral enantiomers of 〚Cp*M(2-alkyl-Phenoxo)〛 〚BF4〛 {M = Rh, Ir} by the trisphat anion. CR CHIM 2002. [DOI: 10.1016/s1631-0748(02)01372-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
21
|
Modica E, Zanaletti R, Freccero M, Mella M. Alkylation of amino acids and glutathione in water by o-quinone methide. Reactivity and selectivity. J Org Chem 2001; 66:41-52. [PMID: 11429928 DOI: 10.1021/jo0006627] [Citation(s) in RCA: 147] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
o-Quinone methide (1) has been produced in water both thermally and photochemically from (2-hydroxybenzyl)trimethylammonium iodide (2). Michael addition reactions of 1 to various amines, and sulfides, including amino acids and glutathione have been carried out, obtaining alkylated adducts (3-16) in fairly good to quantitative yields. The reaction rate and selectivity of 1 toward nitrogen and sulfur nucleophiles, in competition with the hydration reaction, have been investigated at different pH by laser flash photolysis technique. The observed reactivity spans 7 orders of magnitude on passing from water (kNu = 5.8 M-1 s-1) to the most reactive nucleophile (2.8 x 10(8) M-1 s-1, 2-mercaptoethanol under alkaline conditions). These are the first direct reaction rate measurements of nucleophilic addition to the parent o-quinone methide (1). Competition experiments provided strong kinetic support to the involvement of free 1 as an intermediate in both thermal and photochemical reactions. Furthermore, several alkylation adducts regenerate 1 either by heating (9, 10, 13, and 14) or by irradiation (9, 11-13, 16). Such a thermal and photochemical reversibility of the alkylation process opens a new perspective for the use and application of such adducts as o-QM molecular carriers.
Collapse
Affiliation(s)
- E Modica
- Dipartimento di Chimica Organica, Università di Pavia, V.le Taramelli 10, 27100 Pavia, Italy
| | | | | | | |
Collapse
|
22
|
Amouri H, Vaissermann J, Rager MN, Grotjahn DB. Rhodium-Stabilized o-Quinone Methides: Synthesis, Structure, and Comparative Study with Their Iridium Congeners. Organometallics 2000. [DOI: 10.1021/om0005598] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hani Amouri
- Laboratoire de Chimie Inorganique et Matériaux Moléculaires, Unité de Recherche 7071-CNRS, Université Pierre et Marie Curie, 4 Place Jussieu, Case 42, 75252 Paris Cedex 05, France
| | - Jacqueline Vaissermann
- Laboratoire de Chimie Inorganique et Matériaux Moléculaires, Unité de Recherche 7071-CNRS, Université Pierre et Marie Curie, 4 Place Jussieu, Case 42, 75252 Paris Cedex 05, France
| | - Marie Noelle Rager
- NMR Services of Ecole Nationale Supérieure de Chimie de Paris, 11 Rue Pierre et Marie Curie, 75231 Paris Cedex 05, France
| | - Douglas B. Grotjahn
- Department of Chemistry, 5500 Campanile Drive, San Diego State University, San Diego, California 92182-1030
| |
Collapse
|
23
|
Amouri H, Vaissermann J, Rager MN, Grotjahn DB. Stable o-Quinone Methide Complexes of Iridium: Synthesis, Structure, and Reversed Reactivity Imparted by Metal Complexation. Organometallics 2000. [DOI: 10.1021/om000073r] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Hani Amouri
- Laboratoire de Chimie Inorganique et Matériaux Moléculaires Unité CNRS 7071, Université Pierre et Marie Curie, 4 Place Jussieu, 75252 Paris Cedex 05, France
| | - Jacqueline Vaissermann
- Laboratoire de Chimie Inorganique et Matériaux Moléculaires Unité CNRS 7071, Université Pierre et Marie Curie, 4 Place Jussieu, 75252 Paris Cedex 05, France
| | - Marie Noelle Rager
- NMR Services of Ecole Nationale Supérieure de Chimie de Paris, 11 Rue Pierre et Marie Curie, 75231 Paris Cedex 05, France
| | - Douglas B. Grotjahn
- Department of Chemistry, 5500 Campanile Drive, San Diego State University, San Diego, California 92182-1030
| |
Collapse
|
24
|
Britt PF, Buchanan AC, Cooney MJ, Martineau DR. Flash vacuum pyrolysis of methoxy-substituted lignin model compounds. J Org Chem 2000; 65:1376-89. [PMID: 10814099 DOI: 10.1021/jo991479k] [Citation(s) in RCA: 213] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The flash vacuum pyrolysis (FVP) of methoxy-substituted beta-O-4 lignin model compounds has been studied at 500 degrees C to provide mechanistic insight into the primary reaction pathways that occur under conditions of fast pyrolysis. FVP of PhCH(2)CH(2)OPh (PPE), a model of the dominant beta-O-4 linkage in lignin, proceeds by C-O and C-C cleavage, in a 37:1 ratio, to produce styrene plus phenol as the dominant products and minor amounts of toluene, bibenzyl, and benzaldehyde. From the deuterium isotope effect in the FVP of PhCD(2)CH(2)OPh, it was shown that C-O cleavage occurs by homolysis and by 1,2-elimination in a ratio of 1.4:1, respectively. Methoxy substituents enhance the homolysis of the beta-O-4 linkage, relative to PPE, in o-CH(3)O-C(6)H(4)OCH(2)CH(2)Ph (o-CH(3)O-PPE) and (o-CH(3)O)(2)-C(6)H(3)OCH(2)CH(2)Ph ((o-CH(3)O)(2)-PPE) by a factor of 7.4 and 21, respectively. The methoxy-substituted phenoxy radicals undergo a complex series of reactions, which are dominated by 1,5-, 1,6-, and 1,4-intramolecular hydrogen abstraction, rearrangement, and beta-scission reactions. In the FVP of o-CH(3)O-PPE, the dominant product, salicylaldehyde, forms from the methoxyphenoxy radical by a 1,5-hydrogen shift to form 2-hydroxyphenoxymethyl radical, 1,2-phenyl shift, and beta-scission of a hydrogen atom. The 2-hydroxyphenoxymethyl radical can also cleave to form formaldehyde and phenol in which the ratio of 1, 2-phenyl shift to beta-scission is ca. 4:1. In the FVP of o-CH(3)O-PPE and (o-CH(3)O)(2)-PPE, products (ca. 20 mol %) are also formed by C-O homolysis of the methoxy group. The resulting phenoxy radicals undergo 1,5- and 1,6-hydrogen shifts in a ratio of ca. 2:1 to the aliphatic or benzylic carbon, respectively, of the phenethyl chain. In the FVP of (o-CH(3)O)(2)-PPE, o-cresol was the dominant product. It was formed by decomposition of 2-hydroxy-3-hydroxymethylbenzaldehyde and 2-hydroxybenzyl alcohol, which are formed from a complex series of reactions from the 2, 6-dimethoxyphenoxy radical. The key step in this reaction sequence was the rapid 1,5-hydrogen shift from 2-hydroxy-3-methoxybenzyloxy radical to 2-hydroxymethyl-6-methoxyphenoxy radical before beta-scission of a hydrogen atom to give the substituted benzaldehyde. The 2-hydroxybenzyl alcohols rapidly decompose under the reaction conditions to o-benzoquinone methide and pick up hydrogen from the reactor walls to form o-cresol.
Collapse
Affiliation(s)
- P F Britt
- Chemical and Analytical Sciences Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831-6197, USA
| | | | | | | |
Collapse
|
25
|
Chrostowska A, Gracian F, Sotiropoulos JM, Pfister-Guillouzo G, Wojciechowski K. UV Photoelectron Spectroscopy Studies of the Products of Thermal Extrusion of Sulfur Dioxide from Benzosultams. European J Org Chem 2000. [DOI: 10.1002/(sici)1099-0690(200001)2000:2<313::aid-ejoc313>3.0.co;2-i] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
26
|
|
27
|
Qiao GG, Lenghaus K, Solomon DH, Reisinger A, Bytheway I, Wentrup C. 4,6-Dimethyl-o-quinone Methide and 4,6-Dimethylbenzoxete. J Org Chem 1998. [DOI: 10.1021/jo981445x] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
28
|
Tomioka H. Versatile Reactions Undergone by Carbenes and Nitrenes in Noble Gas Matrices at Cryogenic Temperatures. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 1998. [DOI: 10.1246/bcsj.71.1501] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
29
|
Dorrestijn E, Pugin R, Ciriano Nogales MV, Mulder P. Thermal Decomposition of Chroman. Reactivity of o-Quinone Methide. J Org Chem 1997. [DOI: 10.1021/jo9701694] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Edwin Dorrestijn
- Center for Chemistry and the Environment, Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | - Raphaël Pugin
- Center for Chemistry and the Environment, Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | - M. Victoria Ciriano Nogales
- Center for Chemistry and the Environment, Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| | - Peter Mulder
- Center for Chemistry and the Environment, Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, P.O. Box 9502, 2300 RA Leiden, The Netherlands
| |
Collapse
|
30
|
|
31
|
Adam W, Sauter M, Zünkler C. Preparation of 2H-Benzoxetes by Photoinduced [2 + 2] Cycloaddition of Quinone Methides, Accessible by Dimethyldioxirane (DMD) Oxidation of 2,3-Dimethylbenzofurans. ACTA ACUST UNITED AC 1994. [DOI: 10.1002/cber.19941270622] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
32
|
|
33
|
Sander W, Morawietz J. Matrix isolation of a reactive o-quinoid compound - 6-methylene-2,4-cyclohexadien-1-imine. Tetrahedron Lett 1993. [DOI: 10.1016/s0040-4039(00)91961-0] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
34
|
Pfister-Guillouzo G, Gracian F, Senio A, Letulle M, Ripoll JL. The thermal isomerisation benzoazetine - 6-methylene-2,4- cyclohexadien-1-imine: A photoelectron investigation. Tetrahedron Lett 1992. [DOI: 10.1016/0040-4039(92)89023-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|