Palladium-Catalysed Multicomponent Aminocarbonylation of Aryl or Heteroaryl Halides with [Mo(CO)6] and Aryl- or ­Heteroarylamines Using Conventional Heating



Di(hetero)arylamides have been synthesized in short reaction times by palladium-catalysed multicomponent aminocarbonylation of either electron-deficient or electron-rich heteroaryl halides and p-iodoanisole with several arylamines bearing either electron-donating or -withdrawing groups and aminopyridines using [Mo(CO)6] as a solid CO source and conventional heating. Starting from heteroaryl bromides, a palladacycle with tBu3PHBF4 as ligand is required together with DBU as a base in dioxane and a temperature of 125 °C. From (hetero)aryl iodides, Pd(OAc)2 without a ligand and DBU were used in dioxane at 110 °C. Under the latter conditions we were able to apply this reaction to deactivated aminopyridines to obtain the corresponding di(hetero)arylamides. We have demonstrated that these reactions can be performed under conventional heating (110–125 °C) to yield the corresponding di(hetero)arylamides in moderate-to-high yields in short reaction times (from 1–3 h) with no need for MW irradiation. A N-substituted isoindoline-1,3-dione from 2-iodobenzoic acid or methyl 2-iodobenzoate and p-anisidine through a one-step carbonylative cyclization reaction was also obtained. Thus, we have extended the scope of thispalladium-catalysed aminocarbonylation reaction with [Mo(CO)6] to several (hetero)aryl substrates using conventional heating. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)