Exploring chemical diversity via a modular reaction pairing strategy

The efficient synthesis of an 80-member library of unique benzoxathiazocine 1,1-dioxides by a microwave-assisted, intermolecular nucleophilic aromatic substitution (SNAr) diversification pathway is reported. Eight benzofused sultam cores were generated by means of a sulfonylation/SNAr/Mitsunobu reaction pairing protocol, and subsequently diversified by intermolecular SNAr with ten chiral, non-racemic amine/amino alcohol building blocks. Computational analyses were employed to explore and evaluate the chemical diversity of the library.

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Nitroxide radicals appended to phthalonitriles: synthesis, structural characterization and photophysical properties

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229621001832 ◽

2021 ◽

Vol 77 (3) ◽

pp. 137-143

Author(s):

Ismail Fidan ◽

Emel Onal ◽

Catherine Hirel

Keyword(s):

Magnetic Measurements ◽

Photophysical Properties ◽

Nucleophilic Aromatic Substitution ◽

Structural Studies ◽

Aromatic Substitution ◽

Nitronyl Nitroxide ◽

X Ray Diffraction ◽

X Ray ◽

Microwave Assisted ◽

Ft Ir

The syntheses of 4-[4-(4,4,5,5-tetramethyl-2-imidazoline-3-oxide-1-oxyl-2-yl)phenoxy]phthalonitrile (3, C21H19N4O3) and 4-[4-(4,4,5,5-tetramethyl-2-imidazoline-1-oxyl-2-yl)phenoxy]phthalonitrile (4) were carried out by microwave-assisted nucleophilic aromatic substitution of 4-nitrophthalonitrile (2) by the pre-formed 2-(4-hydroxyphenyl)-4,4,5,5-tetramethyl-2-imidazoline-3-oxide-1-oxyl (1). Compounds 3 and 4 were characterized unambiguously by a rich array of analyses, such as melting point, FT–IR, MALDI–TOF MS, elemental analysis, UV–Vis, CV, EPR, magnetic measurements and single-crystal X-ray diffraction. Structural studies demonstrate that the C—H...X and C—X...π (X = O and N) interactions in the radical nitronyl nitroxide groups play an important role in the assembly of the crystal structures. Moreover, cyclic voltammetry analyses show that the phthalonitrile substituent retains the redox properties of the Ullman radicals.

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The Versatility of the Aryne–Imine–Aryne Coupling for the Synthesis of Acridinium Photocatalysts

Synlett ◽

10.1055/s-0040-1720349 ◽

2021 ◽

Author(s):

Christof Sparr ◽

Valeriia Hutskalova

Keyword(s):

Substitution Reaction ◽

Precious Metal ◽

Photophysical Properties ◽

Cation Radical ◽

Coupling Reaction ◽

Nucleophilic Aromatic Substitution ◽

The Novel ◽

Aromatic Substitution ◽

Efficient Synthesis

AbstractThe increasing use of acridinium photocatalysts as sustainable alternative to precious metal-based counterparts encourages the design and efficient synthesis of distinct catalyst structures. Herein, we report our exploration of the scope of the aryne–imine–aryne coupling reaction combined with a subsequent acridane oxidation for a short two-step approach towards various acridinium salts. The photophysical properties of the novel photocatalysts were investigated and the practical value was demonstrated by a cation-radical accelerated nucleophilic aromatic substitution reaction.

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Efficient Synthesis of 3,4-Disubstituted 7-Azaindoles Employing SEM as a Dual Protecting–Activating Group

Synlett ◽

10.1055/s-0039-1690735 ◽

2019 ◽

Vol 30 (20) ◽

pp. 2273-2278 ◽

Cited By ~ 1

Author(s):

Piroska Gyárfás ◽

János Gerencsér ◽

Warren S. Wade ◽

László Ürögdi ◽

Zoltán Novák ◽

...

Keyword(s):

Functional Groups ◽

Efficient Method ◽

Reaction Times ◽

Nucleophilic Aromatic Substitution ◽

Aromatic Substitution ◽

Efficient Synthesis ◽

Mild Conditions

An efficient method for nucleophilic aromatic substitution on 7-azaindoles has been developed. The reaction is facilitated by the unique dual influence of SEM as both protecting and activating group, permitting mild conditions and short reaction times that are compatible with sensitive functional groups. The method is suitable for the synthesis of a broad range of products, most notably ethers.

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Greening the organic chemistry laboratory: a comparison of microwave-assisted and classical nucleophilic aromatic substitution reactions

Green Chemistry Letters and Reviews ◽

10.1080/17518253.2015.1065010 ◽

2015 ◽

Vol 8 (2) ◽

pp. 39-42 ◽

Cited By ~ 3

Author(s):

Devin Latimer ◽

Michael Wiebe

Keyword(s):

Organic Chemistry ◽

Nucleophilic Aromatic Substitution ◽

Chemistry Laboratory ◽

Aromatic Substitution ◽

Substitution Reactions ◽

Microwave Assisted ◽

Organic Chemistry Laboratory

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Microwave-assisted Efficient Synthesis of Isatins and spiro-Thiadiazolines under Green Chemistry Protocol

Journal of Scientific Research ◽

10.3329/jsr.v2i2.3731 ◽

2010 ◽

Vol 2 (2) ◽

pp. 322-329 ◽

Cited By ~ 3

Author(s):

M. M. Hossain ◽

M. A. Foysal ◽

M. Mahabub ◽

Al- Amin

Keyword(s):

Schiff Base ◽

Green Chemistry ◽

Schiff Bases ◽

Aromatic Amines ◽

Electrophilic Aromatic Substitution ◽

Aromatic Substitution ◽

Efficient Synthesis ◽

Microwave Assisted ◽

Primary Aromatic Amines ◽

Mw Irradiation

MW-assisted treatment of oximinoacetanilides obtained from substituted primary aromatic amines was carried out in conc. H2SO4 medium for 5-10 sec to give cyclic amides (isatins) through intramolecular cyclization by means of electrophilic aromatic substitution. Isatins reacted with thiosemicarbazide under MW-condition gave the corresponding Schiff-bases. The Schiff-bases undergo cyclization in presence of minimal Ac2O under MW-irradiation for 3-4 min to give the spiro-thiadiazoline acetyl derivatives in excellent yield. Keywords: Microwave-synthesis; Isatins; Schiff-base; spiro-Thiadiazoline; Green chemistry. © 2010 JSR Publications. ISSN: 2070-0237 (Print); 2070-0245 (Online). All rights reserved. DOI: 10.3329/jsr.v2i2.3731 J. Sci. Res. 2 (2), 322-329 (2010)

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