357653-68-0Relevant academic research and scientific papers
Efficient Palladium-Catalyzed Alkoxycarbonylation of N-Heteroaryl Chlorides - A Practical Synthesis of Building Blocks for Pharmaceuticals and Herbicides
Beller, Matthias,Maegerlein, Wolfganf,Indolese, Adriano F.,Fischer, Christine
, p. 1098 - 1109 (2001)
The alkoxycarbonylation of various N-heteroaryl chlorides was examined in detail. Studies of the butoxycarbonylation of 2- and 3-chloropyridine revealed the importance of selecting both the right phosphine ligand and ligand concentration in order to obtain efficient conversion and selectivity. Amongst the different ligands tested, 1,4-bis(diphenylphosphino)butane (dppb) and 1,1'-bis(diphenylphosphino)ferrocene (dppf) led to the most efficient palladium catalyst systems for the conversion of 2- and 4-chloropyridines and similar heteroaryl chlorides. The best catalytic systems for the alkoxycarbonylation of less activated substrates, such as 3-chloropyridines, were found to be those containing 1,4-bis(dicyclohexylphosphino)butane. Good to excellent yields of a number of N-heterocyclic carboxylic acid esters were realized by applying the appropriate ligand in the right concentration at low catalyst loadings (0.005-0.5 mol percent Pd). For the first time catalyst turnover numbers (TON) of up to 13,000 were obtained for the carbonylation of a (hetero)aryl chloride.
Advances in the carbonylation of aryl halides using palladium catalysts
Beller, Matthias,Indolese, Adriano F.
, p. 684 - 687 (2007/10/03)
The palladium-catalyzed carbonylation of aryl halides is shown to be a versatile tool for the synthesis of various benzoic and heteroaromatic acid derivatives. Recent developments from our laboratories in this area are presented.
