Reaction of bis(bis(trimethylsilyl)amido)mercury(II) with 3,3′-disubstituted binaphthols: Cyclization via an intramolecular electrophilic aromatic substitution reaction

Reaction of the mercury(II) amide Hg[N(SiMe3)3]2 with 3,3′-disubstituted binaphthols (HO)2C20H10(R)2-3,3′ (R = SiMe3, SiMe2Ph, SiMePh2, SiPh3) in a 2:1 stoichiometric ratio furnishes four hexacyclic 1,7-disilylsubstituted derivatives of peri-xanthenoxanthene (PXX). Reaction of these two reagents in a 1:1 ratio results in a mixture of the hexacyclic products as well as the related pentacyclic species which contain one hydroxyl group and only one C–O–C ring fusion. The structures of three of the hexacyclic products (R = SiMe3, SiMe2Ph, SiMePh2) and one of the pentacyclic products (R = SiMe3) have been obtained. The reaction of Hg[N(SiMe3)3]2 with the 3,3′-disubstituted binaphthols proceeds via an intramolecular electrophilic aromatic substitution reaction and several intermediates in this process have been detected using NMR (1H and 199Hg) spectroscopy.