2008

CarbonylationO 0305 Efficient Carbonylation Reactions in Phosphonium Salt Ionic Liquids: Anionic

Effects. — The Pd-catalyzed carbonylation of aryl and vinyl halides (I) with carbon monoxide proceeds smoothly in a phosphonium salt ionic liquid as solvent. High to ex-cellent yields are achieved for aryl iodides and bromides, while chlorides and triflates are less effective. Depending on the nucleophile added, the reaction provides access towards carboxylic esters, amides [cf. (IVh)] or acids (V). Best results are achieved us-ing the bromide ionic liquid due to formation of reactive acid bromide intermediates. Solvent-free product isolation and recycling of the ionic liquid containing active Pd cat-alyst is demonstrated. — (MCNULTY*, J.; NAIR, J. J.; ROBERTSON, A.; Org. Lett. 9 (2007) 22, 4575-4578; Dep. Chem., McMaster Univ., Hamilton, Ont. L8S 4M1, Can.; Eng.) — Mischke

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