Pericyclic reactions carbon shift

This reaction does not proceed via a Whitmore 1,2-shift, but instead is a concerted pericyclic [3,3] sigmatropic rearrangement that results in a cyclic ketone, which after tautomerisation, gives the phenol. Furthermore, in this reaction a C-0 bond is broken, rather than made, and a C-C bond is formed thus, it could have been considered under carbon/carbon rearrangements. 

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