Electrophilic substitution of C60F18 into phenols: HF elimination between OH and a 1,3-shifted fluorine giving benzofurano[2′,3′:10,26]hexadecafluoro[60]fullerene and derivatives

Abstract

The reaction of C₆₀F₁₈ with phenol, 2-naphthol and quinol in the presence of ferric chloride leads to initial electrophilic substitution (aryldefluorination). This occurs at both ortho and para positions for phenol, at the ortho position for quinol, and at the relatively hindered but most reactive 1-position for 2-naphthol. It is followed, where sterically favourable, by HF loss either between the OH group and F (rendered adjacent as a result of a 1,3-shift) or to attack of the OH group at an adjacent double bond with loss of a β-fluorine, giving benzofurano[2′,3′:10,26]hexadecafluoro[60]fullerene derivatives. The reaction is accompanied by some complete defluorination leading, in reaction with phenol and with 2-naphthol, to the formation of benzofurano[2′,3′:1,2][60]fullerene and naphtho[2,1:b]furano[d:1,2][60]-fullerene, respectively. The mechanism of base-catalysed reaction of phenols with C₆₀Cl₆ is re-evaluated.