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Insight into trifluoromethylation - experimental electron density for Togni reagent I.

ABSTRACT: 3,3-Dimethyl-1-(trifluoromethyl)-1,3-dihydro-1-λ3,2-benziodoxole represents a popular reagent for trifluoromethylation. The σ hole on the hypervalent iodine atom in this "Togni reagent" is crucial for adduct formation between the reagent and a nucleophilic substrate. The electronic situation may be probed by high resolution X-ray diffraction: the experimental charge density thus derived shows that the short intermolecular contact of 3.0 Å between the iodine and a neighbouring oxygen atom is associated with a local charge depletion on the heavy halogen in the direction of the nucleophile and visible polarization of the O valence shell towards the iodine atom. In agreement with the expectation for λ3-iodanes, the intermolecular O⋯I-C_aryl halogen bond deviates significantly from linearity.

SUBMITTER: Wang R

PROVIDER: S-EPMC9087471 | biostudies-literature | 2018 Oct

REPOSITORIES: biostudies-literature

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Insight into trifluoromethylation - experimental electron density for Togni reagent I.

Wang R R Kalf I I Englert U U

RSC advances 20181005 60

3,3-Dimethyl-1-(trifluoromethyl)-1,3-dihydro-1-λ3,2-benziodoxole represents a popular reagent for trifluoromethylation. The σ hole on the hypervalent iodine atom in this "Togni reagent" is crucial for adduct formation between the reagent and a nucleophilic substrate. The electronic situation may be probed by high resolution X-ray diffraction: the experimental charge density thus derived shows that the short intermolecular contact of 3.0 Å between the iodine and a neighbouring oxygen atom is asso ...[more]

PMID: 35548651

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