33696-26-3Relevant articles and documents
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)
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.
