Oxazolines. XXII. Nucleophilic aromatic substitution on aryl oxazolines. Efficient approach to unsymmetrically substituted biphenyls and o-alkyl benzoic acids

1975 ◽  
Vol 97 (25) ◽  
pp. 7383-7385 ◽  
Author(s):  
A. I. Meyers ◽  
Edward D. Mihelich
Keyword(s):  
Nucleophilic Aromatic Substitution ◽  
Benzoic Acids ◽  
Aromatic Substitution ◽  
Efficient Approach

Uncatalyzed CO2Li-Mediated SNAr Reaction of Unprotected Benzoic Acids via Silicon Trickery

2016 ◽  
Vol 69 (3) ◽  
pp. 307 ◽  
Author(s):  
Mickael Belaud-Rotureau ◽  
Anne-Sophie Castanet ◽  
Thi Huu Nguyen ◽  
Jacques Mortier
Keyword(s):  
Methoxy Group ◽  
Intermediate Formation ◽  
Coupling Reaction ◽  
Nucleophilic Aromatic Substitution ◽  
Direct Access ◽  
Nucleophilic Attack ◽  
Benzoic Acids ◽  
Aromatic Substitution ◽  
Snar Reaction ◽  
Ketone Formation

The alkyl and aryllithium nucleophilic aromatic substitution (SNAr) displacement of a fluoro or methoxy group from unprotected 2-fluoro/methoxybenzoic acids is discussed. It was discovered that a TMS group located at the C6-position ortho to the carboxyl group shields effectively the carboxylate against nucleophilic attack, thus reducing dramatically ketone formation, and reorients nucleophilic substitution to the C2-position. The reactions with fluoro-substituted substrate 7 proceed efficiently; in contrast, the use of methoxy-functionalized benzoic acid 8 only affords moderate yields with s-BuLi and PhLi. This uncatalyzed coupling reaction, which provides a direct access to biaryl compounds, presumably proceeds by an addition–elimination sequence via intermediate formation of a resonance-stabilized pentavalent silalactone-Meisenheimer complex.

Corroles bearing diverse coumarin units — synthesis and optical properties

2011 ◽  
Vol 15 (09n10) ◽  
pp. 1011-1023 ◽  
Author(s):  
Mariusz Tasior ◽  
Roman Voloshchuk ◽  
Yevgen M. Poronik ◽  
Tomasz Rowicki ◽  
Daniel T. Gryko
Keyword(s):  
Optical Properties ◽  
Spectroscopic Properties ◽  
Nucleophilic Aromatic Substitution ◽  
Sonogashira Coupling ◽  
Aromatic Substitution ◽  
Diverse Range ◽  
Efficient Approach ◽  
General Methodology ◽  
Direct Condensation

Two strategies were shown to be efficient in the construction of corroles with appended coumarin units. Direct condensation of formyl-coumarins with dipyrromethanes leads to a diverse range of trans-A2B-corroles in moderate yields. We showed that the strategy consisting of synthesis of various hydroxycoumarins followed by nucleophilic aromatic substitution with pentafluorobenzaldehyde and subsequent condensation of the resulting coumarin-aldehyde with dipyrromethanes is the most general methodology for the preparation of such dyads. The second, more demanding but also more efficient approach is based on Sonogashira coupling of ethynylphenylcorroles with suitably functionalized bromocoumarins. A broad range of structurally diverse coumarins were employed with absorption ranging from 300 to 460 nm. Spectroscopic properties of all eight dyads studied suggest that the linker components are weakly electronically coupled.

scholarly journals Synthesis and stability of strongly acidic benzamide derivatives

2018 ◽  
Vol 14 ◽  
pp. 523-530 ◽  
Author(s):  
Frederik Diness ◽  
Niels J Bjerrum ◽  
Mikael Begtrup
Keyword(s):  
Organic Acids ◽  
Aqueous Solutions ◽  
Cross Coupling ◽  
Nucleophilic Aromatic Substitution ◽  
Benzoic Acids ◽  
Aromatic Substitution ◽  
Substitution Reactions ◽  
Dilute Aqueous Solutions ◽  
Derivatives Of ◽  
Benzamide Derivatives

Reactivity studies of strong organic acids based on the replacement of one or both of the oxygens in benzoic acids with the trifluoromethanesulfonamide group are reported. Novel derivatives of these types of acids were synthesized in good yields. The generated N-triflylbenzamides were further functionalized through cross-coupling and nucleophilic aromatic substitution reactions. All compounds were stable in dilute aqueous solutions. Studies of stability under acidic and basic conditions are also reported.

scholarly journals Machine learning meets mechanistic modelling for accurate prediction of experimental activation energies

2021 ◽  
Author(s):  
Kjell Jorner ◽  
Tore Brinck ◽  
Per-Ola Norrby ◽  
David Buttar
Keyword(s):  
Machine Learning ◽  
Activation Energies ◽  
Accurate Prediction ◽  
Nucleophilic Aromatic Substitution ◽  
Aromatic Substitution ◽  
Mechanistic Modelling

Hybrid reactivity models, combining mechanistic calculations and machine learning with descriptors, are used to predict barriers for nucleophilic aromatic substitution.

Enantioselective Nucleophilic Aromatic Substitution Reaction of Azlactones to Synthesize Quaternary α-Amino Acid Derivatives

Synlett ◽  
2020 ◽  
Author(s):  
Xiaohua Liu ◽  
Yi Li ◽  
Hao Pan ◽  
Wang-Yuren Li ◽  
Xiaoming Feng
Keyword(s):  
Hydrogen Bonding ◽  
Charge Transfer ◽  
Amino Acid ◽  
Substitution Reaction ◽  
Nucleophilic Aromatic Substitution ◽  
Amino Acid Derivatives ◽  
Amino Acid Esters ◽  
Aromatic Substitution ◽  
Charge Transfer Interaction ◽  
Acid Esters

AbstractAn asymmetric organocatalytic nucleophilic aromatic substitution reaction of azlactones with electron-deficient aryls was established. A variety of α-aryl α-alkyl α-amino acid esters and peptides were obtained in decent yields and stereoselectivities. A new bifunctional catalytic mode involving charge-transfer interaction and hydrogen bonding is proposed to explain the enantioselectivity.

Nucleophilic aromatic substitution using Et3SiH/cat. t-Bu-P4 as a system for nucleophile activation

2007 ◽  
pp. 2264 ◽  
Author(s):  
Masahiro Ueno ◽  
Misato Yonemoto ◽  
Masahiro Hashimoto ◽  
Andrew E. H. Wheatley ◽  
Hiroshi Naka ◽  
...  
Keyword(s):  
Nucleophilic Aromatic Substitution ◽  
Aromatic Substitution ◽  
Nucleophile Activation
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