Aromatic C-F activation by complexes containing the {Pt<inf>2</inf>S <inf>2</inf>} core via nucleophilic substitution: A combined experimental and theoretical study

Ainara Nova, Rubén Mas-Ballesté, Gregori Ujaque, Pilar González-Duarte, Agustí Lledós

Research output: Contribution to journalArticleResearchpeer-review

23 Citations (Scopus)

Abstract

The C-F bond activation of perfluorobenzene and perfluoropyridine have been achieved by means of the complex [Pt2(μ-S)2(dppp) 2], where dppp denotes 1,3-bis(diphenylphosphino)propane. The reaction with the first substrate requires a long time (five days) and high temperature (reflux in toluene) to yield [Pt(o-S2C6F 4)(dppp)] and [Pt3(μ3-S)2(dppp) 3]F2, and involves replacement of two fluorides in the ortho position. In contrast, the reaction with perfluoropyridine is much faster (15 min at 0 °C) yielding [Pt2(μ-S){μ-(p-SC 5F4N)}(dppp)2]F, which implies the C-F activation in the para position with respect the pyridine nitrogen. The mechanism of both reactions has been studied computationally and the geometries of the transition states are consistent with an SNAr mechanism where a sulfido bridging ligand replaces the fluoride anion. The energy barriers corresponding to the first and the second fluoride substitution are 131.7 and 137.1 kJ mol-1 for perfluorobenzene and 85.9 and 142.7 kJ mol -1 for perfluoropyridine, respectively. The different energy barrier of the first substitution explains the different experimental conditions required and the various products obtained for these reactions. © The Royal Society of Chemistry 2009.
Original languageEnglish
Pages (from-to)5980-5988
JournalDalton Transactions
Issue number30
DOIs
Publication statusPublished - 10 Aug 2009

Fingerprint

Dive into the research topics of 'Aromatic C-F activation by complexes containing the {Pt<inf>2</inf>S <inf>2</inf>} core via nucleophilic substitution: A combined experimental and theoretical study'. Together they form a unique fingerprint.

Cite this