Intermediates in nucleophilic aromatic substitutions. I. Meisenheimer complexes of dinitro-substituted aromatic ethers

1967 ◽  
Vol 32 (8) ◽  
pp. 2506-2511 ◽  
Author(s):  
William E. Byrne ◽  
Eleanor J. Fendler ◽  
Janos H. Fendler ◽  
Claibourne E. Griffin
Keyword(s):  
Meisenheimer Complexes ◽  
Nucleophilic Aromatic Substitutions

Intermediates in nucleophilic aromatic substitutions. III. Meisenheimer complexes of 1-alkoxy-2,4-dinitronaphthalenes

1968 ◽  
Vol 33 (3) ◽  
pp. 977-985 ◽  
Author(s):  
Janos H. Fendler ◽  
Eleanor J. Fendler ◽  
William E. Byrne ◽  
Claibourne E. Griffin
Keyword(s):  
Meisenheimer Complexes ◽  
Nucleophilic Aromatic Substitutions

On the Mechanism of the Dimethyldioxirane Oxidation of σHAdducts (Meisenheimer Complexes) Generated from Nitroarenes and Carbanions

2000 ◽  
Vol 65 (4) ◽  
pp. 1099-1101 ◽  
Author(s):  
Waldemar Adam ◽  
Mieczyslaw Makosza ◽  
Cong-Gui Zhao ◽  
Marek Surowiec
Keyword(s):  
Meisenheimer Complexes

Electrochemical Preparation and Characterization of Meisenheimer Complexes of Trinitrofluorenone with Pyrrole, Indole, and Carbazole

2002 ◽  
Vol 14 (3) ◽  
pp. 1067-1074 ◽  
Author(s):  
Nobuo Ozawa ◽  
Hiroko Seki ◽  
Takashi Kitamura ◽  
Hiroshi Kokado ◽  
Tsutomu Ishikawa ◽  
...  
Keyword(s):  
Electrochemical Preparation ◽  
Meisenheimer Complexes

Reactions of the ambident super-electrophile series: the 2-(nitroaryl)-4,6-dinitrobenzotriazole 1-oxides with isopropoxide ion. Pathways of decomposition of the anionic σ-adducts

1994 ◽  
Vol 72 (1) ◽  
pp. 218-226 ◽  
Author(s):  
Julian M. Dust ◽  
Erwin Buncel
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Nuclear Magnetic Resonance Spectroscopy ◽  
Adduct Formation ◽  
Resonance Spectroscopy ◽  
Energy Profiles ◽  
Meisenheimer Complexes ◽  
Bond Scission ◽  
Relative Selectivity

To elucidate the reactivity of super-electrophiles such as 4,6-dinitrobenzofuroxan as compared to normal electrophiles such as 1,3,5-trinitrobenzene, reaction of isopropoxide ion (iPrO−) with a series of ambident super-electrophiles was studied by 400 MHz 1H nuclear magnetic resonance spectroscopy. The 2-(nitroaryl)-4,6-dinitrobenzotriazole 1-oxides, 1–3, possess both a super-electrophilic (C-7) site and a normal electrophilic (C-1′) site. Nucleophiles can demonstrate selectivity for attack at C-7, which leads to formation of persistent anionic σ-adducts (Meisenheimer complexes), as compared to C-1′, which leads to N-2:C-1′ bond scission. The most reactive substrate, 2-(2′,4′,6′-trinitrophenyl)-4,6-dinitrobenzotriazole 1-oxide (Pi-DNBT, 1) was found to be the least selective substrate in C-7 adduct formation, while 2-(2′,4′-dinitrophenyl)- and 2-(4′-nitrophenyl)-4,6-dinitrobenzotriazole 1-oxides (DNP-DNBT, 2, and NP-DNBT, 3, respectively) showed increasing selectivity towards iPrO−, in turn. These results are discussed on the basis of overall selectivity for C-7 adduct formation and the relative selectivity of iPrO− as compared to methoxide and tert-butoxide ions. The conclusions are illustrated using comparative energy profiles. In terms of pathways for decomposition of the adducts, the C-7 adducts decompose via dissociation back to substrate and nucleophile and, thence, through C-1′ adduct formation to the scission products. However, for 1, the C-7 adduct 1a has now been found to decompose to 7-isopropyl-2-picryldinitrobenzotriazole, 1c. The possible mechanism of this formal internal redox will be discussed.

Nucleophilic aromatic substitutions on 4,5-dicyanopyridazine. Part 2: Nitrogen nucleophiles

Tetrahedron ◽  
2013 ◽  
Vol 69 (16) ◽  
pp. 3475-3479 ◽  
Author(s):  
Renzo Alfini ◽  
Elisa Calamai ◽  
Antonella Salvini ◽  
Donatella Giomi
Keyword(s):  
Nitrogen Nucleophiles ◽  
Nucleophilic Aromatic Substitutions
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