Anilide activation of adjacent C-H bonds in the palladium-catalysed Fujiwara-Moritani reaction.

Journal article

The Pd(II)-catalysed oxidative counterpart of the Heck reaction, originally described by Fujiwara and Moritani, has been studied in detail by a combination of NMR, single-crystal X-ray diffraction and substrate variation. The process involves a palladacycle that is a true intermediate in catalysis. Pd(OAc)(2) is first converted into a more electrophilic palladium species for effective catalysis, defining the main role of added acid. In the course of these studies, three palladacyclic intermediates have been characterised by X-ray diffraction, firstly the directly produced acetate complex 1, the camphorsulfonate complex 2, and additionally tosylate 3, isolated from a reacting system, demonstrating the accessibility of a cationic or comparably electrophilic palladium entity under turnover conditions. The isolated palladacycle 3 is also an effective catalyst. The reaction rate shows a first-order dependency on [anilide] and [Pd], but not on benzoquinone, alkene or p-TsOH. Acid, in the form of p-TsOH, is an essential component, whereas acetate is dispensable. A crossover experiment involving distinct substitution in reactant and palladacycle demonstrates that the palladacycle is directly involved in the catalysis.

Authors: Rauf, W; Thompson, A; Brown, J

• Publication status: Published
• Journal: Dalton transactions (Cambridge, England : 2003)
• Volume: 39
• Issue: 43
• Pages: 10414-10421
• Publication date: 2010-11-01
• DOI: 10.1039/c0dt00378f
• EISSN: 1477-9234
• ISSN: 1477-9226
• Language: English