Synthesis of Aromatic and Aliphatic Di-, Tri-, and Tetrasulfonic Acids

Synlett ◽  
2020 ◽  
Vol 31 (10) ◽  
pp. 945-952
Author(s):  
Jens Christoffers ◽  
Mathias S. Wickleder
Keyword(s):  
Nucleophilic Aromatic Substitution ◽  
Electrophilic Aromatic Substitution ◽  
Aromatic Substitution ◽  
Nucleophilic Substitutions ◽  
Sulfonic Acids ◽  
Subsequent Oxidation ◽  
Aromatic Substrates ◽  
Diazonium Ions ◽  
Metal Organic

Oligosulfonic acids are promising linker compounds for coordination polymers and metal-organic frameworks, however, compared to their carboxylic acid congeners, often not readily accessible by established synthetic routes. This Account highlights the synthesis of recently developed aromatic and aliphatic di-, tri- and tetrasulfonic acids. While multiple electrophilic sulfonations of aromatic substrates are rather limited, the nucleophilic aromatic substitution including an intramolecular variant, the Newman–Kwart rearrangement, allows the flexible introduction of up to four sulfur-containing moieties at an aromatic ring. Sulfonic acids are then accessed by oxidation of thiols, thioethers, or thioesters either directly with hydrogen peroxide or in two steps with chlorine (generated in situ from N-chlorosuccinimide/hydrochloric acid) to furnish sulfochlorides which are subsequently hydrolyzed. In the aliphatic series, secondary alcohols as starting materials are converted into thioethers, thioesters, or thiocarbonates by nucleophilic substitutions, which are also subsequently oxidized to furnish sulfonic acids.1 Introduction2 Electrophilic Aromatic Substitution3 Nucleophilic Aromatic Substitution3.1 Intermolecular SNAr3.2 Intermolecular with Subsequent Oxidation3.3 Intramolecular with Subsequent Oxidation4 Nucleophilic Aliphatic Substitution with Subsequent Oxidation5 Oxidation5.1 Oxidation of Thiocarbonates5.2 Oxidation of Thioethers5.3 Oxidation of Thioesters6 Thermolysis of Neopentylsulfonates7 Functionalization via Diazonium Ions8 Conclusion

A Copper Halide Promoted Regioselective Halogenation of Coumarins Using N-Halosuccinimide as Halide Source

Synlett ◽  
2019 ◽  
Vol 30 (05) ◽  
pp. 630-634 ◽  
Author(s):  
Min Zhang ◽  
Jinling Su ◽  
Yan Zhang ◽  
Mingren Chen ◽  
Weiming Li ◽  
...  
Keyword(s):  
Metal Halide ◽  
Regioselective Synthesis ◽  
Electrophilic Aromatic Substitution ◽  
Aromatic Substitution ◽  
Copper Halide ◽  
Experimental Conditions ◽  
Heteroaromatic Compounds ◽  
Convenient Approach ◽  
In Situ Generation

A safe, convenient, and regioselective synthesis of 3-halo coumarins using a metal halide (CuX2 alone or with ZnX2) promoted halogenation with N-halosuccinimide (NXS) as halide source is reported. The synthesis involved the steady in situ generation of highly reactive positive halogen (X+) by the coordination of copper or zinc with the N-halosuccinimide and subsequent electrophilic aromatic substitution of the electron-deficient coumarins. This procedure works well also for the halogenation of less electron-rich naphthoquinones, flavones, and methoxypsoralen in moderate to quantitative yields. This protocol features simple experimental conditions using readily available inexpensive reagents and provides a convenient approach to the chlorination or bromination of some useful heteroaromatic compounds.

scholarly journals Multisubstituted phthalonitriles for phthalocyanine synthesis

2004 ◽  
Vol 08 (11) ◽  
pp. 1293-1299 ◽  
Author(s):  
Jianghong Wang ◽  
Ashot Kh. Khanamiryan ◽  
Clifford C. Leznoff
Keyword(s):  
Nickel Catalyst ◽  
Nucleophilic Aromatic Substitution ◽  
Electrophilic Aromatic Substitution ◽  
Aromatic Substitution ◽  
Substitution Reactions ◽  
Dibromoisocyanuric Acid

3,4,5,6-tetrafluorophthalonitrile and 3,4,5,6-tetrachlorophthalonitrile were used as substrates with various phenoxides to prepare 3,4,6-trihalo-5-p-substitutedphenoxyphthalonitriles, containing four substituents other than hydrogen, by nucleophilic aromatic substitution reactions. Subsequent reactions with unsymmetrical catechols gave tetrasubstitutedphthalonitriles, having four different substituents. In one instance, attempts to displace the last remaining fluoro group by an octanoxide nucleophile led to substitution of a p-methylphenoxy group, showing that phenoxy substituents are also labile in nucleophilic aromatic substitution reactions on phthalonitriles. Alternatively, 4,5-dimethoxyphthalonitrile or 4,5-dineopentoxyphthalonitrile underwent electrophilic aromatic substitution reactions with dibromoisocyanuric acid to give their respective 3,6-dibromophthalonitriles. Coupling of these bromophthalonitriles with tri(n-butyl)phenylylethynyltin and tri(n-butyl)vinyltin in the presence of a nickel catalyst gave 4,5-dimethoxy-3,6-bisphenylethy nylphthalonitrile, 3-bromo-4,5-dimethoxy-6-phenylethynylphthalonitrile, 4,5-dineopentoxy-3,6-bisphenylethynylphthalonitrile, 3-bromo-4,5-dineopentoxy-6-phenylethynylphthalonitrile, 4,5-dimethoxy-3,6-vinylphthalonitrile and 3-bromo-4,5-dimethoxy-6-vinylphthalonitrile. Reductions in the coupling steps sometimes led to 4,5-dimethoxy-3-phenylethynylphthalonitrile and 4,5-dimethoxy-3-vinylphthalonitrile.

Preparation of Benzene Derivatives: The Yu/Baran Synthesis of (+)-Hongoquercin A

2017 ◽  
Author(s):  
Douglass F. Taber
Keyword(s):  
Electrophilic Aromatic Substitution ◽  
University Of Michigan ◽  
Aromatic Substitution ◽  
Blocking Group ◽  
University Of Texas ◽  
University Of Houston ◽  
National University ◽  
Reformatsky Reagent ◽  
The University

Lutz Ackermann of the Georg-August-Universität Göttingen oxidized (Org. Lett. 2013, 15, 3484) the anisole derivative 1 to the phenol 2. Melanie S. Sanford of the University of Michigan devised (Org. Lett. 2013, 15, 5428) complementary condi­tions for either para acetoxylation of 3, illustrated, to give 4, or meta acetoxylation. Lukas J. Goossen of the Technische Universität Kaiserlautern developed (Synthesis 2013, 45, 2387) conditions for the cascade alkoxylation/decarboxylation of 5 to give 6. Cheol-Hong Cheon of Korea University showed (J. Org. Chem. 2013, 78, 12154) that the boronic acid of 7 could act as a blocking group during electrophilic aromatic substitution or, as illustrated, as an ortho directing group. It could then be removed by protodeboronation, leading to 8. Jun Wu of Zhejiang University coupled (Synlett 2013, 24, 1448) the phenol 9 with the bromo amide 10 to give an ether that, on exposure to KOH at elevated temperature, rearranged to the intermediate amide, that was then hydrolyzed to 11. Dong-Shoo Shin of Changwon National University reported (Tetrahedron Lett. 2013, 54, 5151) a similar protocol (not illustrated) to prepare unsubsti­tuted anilines. Guangbin Dong of the University of Texas, Austin used (J. Am. Chem. Soc. 2013, 135, 18350) a variation on the Catellani reaction to add 13 to the ortho bromide 12 to give the meta amine 14. Kei Manabe of the University of Shizuoka found (Angew. Chem. Int. Ed. 2013, 52, 8611) that the crystalline N-for­myl saccharin 16 was a suitable CO donor for the carbonylation of the bromide 15 to the aldehyde 17. John F. Hartwig of the University of California, Berkeley described (J. Org. Chem. 2013, 78, 8250) the coupling of the zinc enolate of an ester (Reformatsky reagent), either preformed or generated in situ, with an aryl bromide 18 to give 19. Olafs Daugulis of the University of Houston developed (Org. Lett. 2013, 15, 5842) conditions for the directed ortho phenoxylation of 20 with 21 to give 22. Yao Fu of the University of Science and Technology of China effected (J. Am. Chem. Soc. 2013, 135, 10630) directed ortho cyanation of 23 with 24 to give 25.

In situ polymerization approach to poly(arylene ether nitrile)-functionalized multiwalled carbon nanotube composite films: thermal, mechanical, dielectric, and electrical properties

2018 ◽  
Vol 25 (1) ◽  
pp. 25-29
Author(s):  
Jiachun Zhong ◽  
Heng Guo ◽  
Jian Yang ◽  
Xiaobo Liu
Keyword(s):  
Carbon Nanotube ◽  
In Situ Polymerization ◽  
Composite Films ◽  
Multiwalled Carbon Nanotube ◽  
Nucleophilic Aromatic Substitution ◽  
Aromatic Substitution ◽  
Multiwalled Carbon ◽  
Arylene Ether ◽  
Quality Dispersion

AbstractPoly(arylene ether nitrile) (PEN)-functionalized multiwalled carbon nanotube (MWNT) composites were successfully prepared via anin situpolymerization method based on the combination of nucleophilic aromatic substitution polymerization with simple acylate-functionalized MWNTs (MWNTs-COCl) in the presence of nitrile monomers. The structure and morphology of PEN-MWNT composites were characterized using Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. The improvement in the thermal stability and mechanical properties of PEN-MWNT films was achieved because of the good-quality dispersion of MWNTs and strong interfacial interaction between the PEN matrix and MWNTs. The most important result is that the dielectric constant and electrical conductivity can be remarkably enhanced by a high MWNT content.

scholarly journals Utilizing the σ-complex stability for quantifying reactivity in nucleophilic substitution of aromatic fluorides

2013 ◽  
Vol 9 ◽  
pp. 791-799 ◽  
Author(s):  
Magnus Liljenberg ◽  
Tore Brinck ◽  
Tobias Rein ◽  
Mats Svensson
Keyword(s):  
Nucleophilic Substitution ◽  
Density Functional ◽  
Reaction Rates ◽  
Nucleophilic Aromatic Substitution ◽  
Aromatic Substitution ◽  
Functional Theory ◽  
Aromatic Substrates ◽  
Complex Approach ◽  
Mechanistic Analysis ◽  
Rate Limiting

A computational approach using density functional theory to compute the energies of the possible σ-complex reaction intermediates, the “σ-complex approach”, has been shown to be very useful in predicting regioselectivity, in electrophilic as well as nucleophilic aromatic substitution. In this article we give a short overview of the background for these investigations and the general requirements for predictive reactivity models for the pharmaceutical industry. We also present new results regarding the reaction rates and regioselectivities in nucleophilic substitution of fluorinated aromatics. They were rationalized by investigating linear correlations between experimental rate constants (k) from the literature with a theoretical quantity, which we call the sigma stability (SS). The SS is the energy change associated with formation of the intermediate σ-complex by attachment of the nucleophile to the aromatic ring. The correlations, which include both neutral (NH3) and anionic (MeO−) nucleophiles are quite satisfactory (r = 0.93 to r = 0.99), and SS is thus useful for quantifying both global (substrate) and local (positional) reactivity in SNAr reactions of fluorinated aromatic substrates. A mechanistic analysis shows that the geometric structure of the σ-complex resembles the rate-limiting transition state and that this provides a rationale for the observed correlations between the SS and the reaction rate.

Mechanism of alkenylation of aromatic substrates with 5-nitro-2-furylvinyl bromide

1986 ◽  
Vol 51 (9) ◽  
pp. 2013-2018
Author(s):  
Ján Hrabovský ◽  
Jaroslav Kováč ◽  
František Považanec
Keyword(s):  
Electrophilic Addition ◽  
Point Of View ◽  
Electrophilic Aromatic Substitution ◽  
Aromatic Substitution ◽  
H Nmr ◽  
Aromatic Substrates ◽  
Nmr Study ◽  
Elimination Pathway

Mechanism has been studied of electrophilic aromatic substitution with (Z)- and (E)-5-nitro-2-furylvinyl bromide in the presence of aluminium(III) chloride. From chemical findings and 1H NMR study it follows that the mechanism can be interpreted as an electrophilic addition-elimination pathway (AdE-E) from the point of view of the vinyl substitution.

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