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Isolation of a Nitromethane Anion in the Calix-Shaped Inorganic Cage.

ABSTRACT: A calix-shaped polyoxometalate, [V₁₂O₃₂]^4- (V12), stabilizes an anion moiety in its central cavity. This molecule-sized container has the potential to control the reactivity of an anion. The highly-reactive cyanate is smoothly trapped by V12 to form [V₁₂O₃₂(CN)]^5-. In the CH₃NO₂ solution, cyanate abstracts protons from CH₃NO₂, and the resultant CH₂NO₂^- is stabilized in V12 to form [V₁₂O₃₂(CH₂NO₂)]^5- (V12(CH₂NO₂)). A crystallographic analysis revealed the double-bond characteristic short bond distance of 1.248 Å between the carbon and nitrogen atoms in the nitromethane anion in V12. ¹H and ¹³C NMR studies showed that the nitromethane anion in V12 must not be exchanged with the nitromethane solvent. Thus, the V12 container restrains the reactivity of anionic species.

SUBMITTER: Kikukawa Y

PROVIDER: S-EPMC7729913 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Isolation of a Nitromethane Anion in the Calix-Shaped Inorganic Cage.

Kikukawa Yuji Y Kitajima Hiromasa H Kuwajima Sho S Hayashi Yoshihito Y

Molecules (Basel, Switzerland) 20201201 23

A calix-shaped polyoxometalate, [V12O32]4- (V12), stabilizes an anion moiety in its central cavity. This molecule-sized container has the potential to control the reactivity of an anion. The highly-reactive cyanate is smoothly trapped by V12 to form [V12O32(CN)]5-. In the CH3NO2 solution, cyanate abstracts protons from CH3NO2, and the resultant CH2NO2< ...[more]

PMID: 33271966

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