Selective preparation of unusual π-adducts of the functional arenes diphenylacetylene, phenol, and benzoic acid with the CpRu+ fragment (Cp = C5Me5)

Abstract

Protonation of [CpRu(OMe)]₂(1) with CF₃SO₃H in tetrahydrofuran (THF) in the presence of methanol yields [CpRu(MeOH)₃](CF₃SO₃)(2); (2) or the reaction mixture (1)+ CF₃SO₃H reacts with one or half an equivalent of diphenylacetylene, benzoic acid, and phenol to give, respectively, [CpRu(η⁶-PhCCPh)](SO₃CF₃)(3), [(CpRu)₂(η⁶, η⁶-PhCCPh)](SO₃CF₃)₂(4), [CpRu(η⁶-PhCO₂H)](SO₃CF₃)(6), and [CpRu(η⁶-PhOH)](SO₃CF₃)(8), whereas the direct reactions of (1) with phenol and benzoic acid yield, respectively, [CpRu(η⁵-PhO)](7) and the zwitterionic derivative [CpRu(η⁶-PhCO₂)](5); the facile interconversion (5)â†�→(6) and (7)â†�→(8) was demonstrated by ¹H NMR.