Do Corroles Stabilize Tetravalent Antimony?

Abstract

AbstractAntimony corrole cations have been prepared by one‐electron oxidation of antimony(III) congeners with silver(I) and copper(II) salts. Isolation and crystallization was successful for the first time, and the X‐ray crystallographic investigation unraveled structural similarities with antimony(III)corroles. EPR experiments showed strong hyperfine interactions of the unpaired electron with the 121Sb (I=5/2) and 123Sb nuclei (I=7/2). A DFT analysis supports the description of the oxidized form as a SbIII corrole radical with less than 2 % SbIV character. In the presence of water or a fluoride source like PF6−, the compounds undergo a redox disproportionation to yield known antimony(III)corroles and either difluorido‐antimony(V)corroles, or bis‐μ‐oxido‐di[antimony(V)corroles] via novel cationic hydroxo‐antimony(V) derivatives.