33696-26-3Relevant academic research and scientific papers
Reactions of the super-electrophile, 2-(2',4'-dinitrophenyl)-4,6-dinitrobenzotriazole 1-oxide, with methoxide and tert-butoxide: basicity and steric hindrance as factors in ?-complex formation versus nucleophilic displacement
Dust, Julian M.,Buncel, Erwin
, p. 978 - 986 (2007/10/02)
The course of the reactions of methoxide and tert-butoxide with 2-(2',4'-dinitrophenyl)-4,6-dinitrobenzotriazole 1-oxide (4) clearly shows that the C-7 electrophilic site is significantly more reactive than the C-1' site of the substrate.The reaction pathways of these alkoxides, which differ in basicity (as a measure of nucleophilicity) and steric bulk, were followed by 400 MHz 1H nuclaear magnetic resonance spectroscopy.While both alkoxides lead to immediate formation of the respective C-7 anionic ?-adducts, a greater percentage of C-7 adduct formation occurs with methoxide as attacking nucleophile.Reactions with excess alkoxide results in attack at C-1' being observed, as well.This leads to formation of metastabile C-1' ?-adducts, whose rapid decomposition results in formation of 2,4-dinitrophenyl ethers and the dinitrobenzotriazole 1-oxyanion in an overall nucleophilic displacement reaction.Under these excess conditions, methoxide also causes a faster rate of displacement than does tert-butoxide as nucleophile.These results are discussed on the basis of the basicity of the nucleophiles, the relative electrophilicity of the positions in the substrate (C-7 versus C-1'), the steric hindrance involved in attack and in the resultant C-7 and C-1' complexes, and in terms of an activation energy/reaction coordinate profile comparing the pathways for attack at the two electrophilic sites. Key words: anionic ?-complexes, super-electrophiles, aromatic nucleophilic substitution (SNAr)
Nucleophilic Substitution of Nitrite in Nitrobenzenes, Nitrobiphenyls and Nitronaphthalenes
Effenberger, Franz,Koch, Markus,Streicher, Willi
, p. 163 - 173 (2007/10/02)
Aromatic compounds, accessible only by multistep procedures, can be synthesized easily by nucleophilic substitution of nitrite in nitrobenzenes, nitrobiphenyls, and nitronaphthalines.Thus, meta-substituted phenols 3, 4, and 7 are obtained from 1,3-dinitrobenzene (1) and meta-substituted nitrobenzenes 6, as well as 3,5-disubstituted phenols 10 and 5-substituted resorcinol derivatives 11 from 3,5-disubstituted nitrobenzenes 9.The unsymmetrically substituted nitrobiphenyls 13, 15, 17, 19, 23, 24, and 26 are also available by nitrite exchange from the corresponding easily accessible dinitrobiphenyls 16, 18, 20, 22, and 25.A nitrite exchange with nucleophiles is easily possible in the 1,5-disubstituted naphthalenes 29, 34, while in the case of the 1,8-disubstituted naphthalenes 31, 36 only the chloro derivative 36 undergoes this exchange under much stronger conditions in low yield.
Arylation with 1,3-Dinitroarenes and Copper(I) t-Butoxide. Scope and Limitations
Carter, Stephen D.,Wallace, Timothy W.
, p. 1601 - 1633 (2007/10/02)
The reaction of 1,3-dinitrobenzene with copper(I) t-butoxide and an iodoarene, which produces a 2,6-dinitrobiphenyl, has been stidied in detail with a variety of substrates.Iodoarenes containing ester, aldehyde, or other halogen functions were effective, but replacement of the iodoarene with a bromoarene, iodoalkyne, or iodoalkene resulted in less efficient coupling, promoting side-reactions.On replacing the second nitro group on the dinitrobenezene with nitrile, ester, amide, or trifluoromethyl groups, little or no coupling was observed.Limiting side-reactions usually involved the decomposition of substrates by t-butoxide via nucleophilic substitution, elimination, or deprotonation.A mechanism based on reversible cupration of the dinitroarene is proposed.
Nucleophilic Aromatic Substitution in Microemulsions
Athanassakis, Vassilios,Bunton, Clifford A.,Buzzaccarini, Francesco de
, p. 5002 - 5009 (2007/10/02)
The rate constants of reaction of 2,4-dinitrofluorobenzene(DNF) with OH- in microemulsions of n-octane, tert-amyl alcohol, and cetyltrimethylammonium bromide (CTABr) and in micelles of CTABr and tert-amyl alcohol can be treated quantitatively by using a pseudophase ion-exchange model and the second-order rate constants in the microemulsion or micelle droplets are larger than that in water, but much smaller than those in moist tertiary alcohols.Reactions of DNF and 2,4-dinitrochlorobenzene (DNC) in microemulsions or micelles containing primary alcohols (n-butyl or benzyl alcohol) give largely ethers as products, and the ethers slowly react giving the 2,4-dinitrophenoxide ion.These reactions of DNF and DNC are faster than reactions with OH- in water but are much slower than those in alcohols.Quantitatively, the relative apparent nucleophilicities of hydroxide and alkoxide ion in the micelle or microemulsion droplet are similar to those in the absence of surfactant.Anionic microemulsions of sodium lauryl sulfate (NaLS) inhibit reactions, but to smaller extent than anionic micelles in water.
