Crawforth, C.M., Fairlamb, I.J.S., Kapdi, A.R., Serrano, J.L., Taylor, R.J.K. and Sanchez, G. (2006) Air stable, phosphine-free anionic palladacyclopentadienyl catalysts: Remarkable halide and pseudohalide effects in Stille coupling. Advanced Synthesis & Catalysis, 348 (4-5). pp. 405-412. ISSN 1615-4150Full text not available from this repository.
The Stille cross-coupling of allylic and benzyl bromides is shown to proceed efficiently using phosphine-free dinuclear anionic palladacyclopentadienyl catalysts possessing bridging (N,O)-imidate ligands. The type of bridging anion influences the catalytic activity considerably. Halide anions such as chloride, bromide or iodide also influence the catalytic activity but to a far lesser extent than the pseudohalide imidate anions (from succinimide or phthalimide). A Baldwin-type cooperative effect is seen with 7a using CuI as a co-catalyst, in the presence of two equivalents of CsF in DMF at 40 °C. In toluene, these additives slow down substrate turnover.
|Keywords:||CC bond formation • copper(I) salts • cross-coupling • halide effects • palladium|
|Institution:||The University of York|
|Academic Units:||The University of York > Chemistry (York)|
|Depositing User:||York RAE Import|
|Date Deposited:||14 Aug 2009 12:53|
|Last Modified:||14 Aug 2009 12:53|
|Publisher:||John Wiley & Sons|