13557-25-0Relevant articles and documents
Evaluation of electrophilic activities of substituted nitroarenes in the VNS reaction with secondary and tertiary carbanions
Blazej,Wilenska,Voynova,Makosza
, p. 2017 - 2030 (2008/12/23)
Relative electrophilic activities of substituted nitroarenes in the vicarious nucleophilic substitution (VNS) reaction with carbanion of chloromethylp-chlorophenyl and bromomethyl phenyl sulfones, 1 and 2, were determined via competitive experiments. The results are in good agreement with relative activities determined earlier in the competitive experiments with carbanion of chloromethyl phenyl sulfone 3 confirming reliability of these data. On the other hand, analogous competitive experiments with tertiary carbanions of chloroform and 1-chloroethyl phenyl sulfone gave results much affected by steric effects thus the VNS reaction with these carbanions cannot be used for evaluation of electrophilic activities of nitroarenes.
Stereochemical studies on the formation of α,β-epoxysulfones using α-chloro-β-hydroxysulfones of known configuration
Grossert, J. Stuart,Sotheeswaran, Subramanian,Dharmarante, H. Ranjith W.,Cameron, T. Stanley
, p. 2870 - 2879 (2007/10/02)
Substitution reactions adjacent to sulfonyl groups are known to proceed with difficulty, and there is evidence to suggest that these may not necessarily proceed by an SN2 pathway.The mechanism of these reactions could be studied in principle by using the conversion of α-chloro-β-hydroxysulfones of known configuration into α,β-epoxysulfones of known configuration.This paper describes results in which this has been attempted.However, the stereochemical aspects of the epoxide formation could not be assigned unequivocally because of the intervention of a very facile "retro-aldol" process when the chlorohydrins are subjected to treatment with bases, although the experimental results do suggest that the reaction does proceed in a regular SN2-like manner, with inversion at carbon.The X-ray crystal structures of two highly substituted α,β-epoxysulfones are presented, thus putting the structures, including stereochemistry, of a range of these compounds of firm ground.
SPECIFIC ORTHO ORIENTATION IN THE VICARIOUS SUBSTITUTION OF HYDROGEN IN AROMATIC NITRO COMPOUNDS WITH CARBANION OF CHLOROMETHYL PHENYL SULFONE
Makosza, M.,Glinka, T.,Kinowski, A.
, p. 1863 - 1868 (2007/10/02)
Vicarious nucleophilic substitution of hydrogen atoms in nitroarenes with chloromethylphenyl sulfone proceeds selectively ortho to the nitro group when carried out in t-BuOK/THF base/solvent system.In the majority of 3-substituted nitrobenzene derivatives substitution occurs at the most hindered position 2.These conditions offer an efficient method of synthesis of 2,6 and 2,3-disubstituted nitrobenzene derivatives.
