A Novel Mode of Reactivity for Gold(I): The Decarboxylative Activation of (Hetero)Aromatic Carboxylic Acids

Abstract

Gold(I) salts are found to mediate the decarboxylation of a variety of aromatic and heteroaromatic carboxylic acids at significatively lower temperatures (as low as 60 8C) than the currently used copper(I) (180-190 8C) and silver(I) (80-140 8C) systems. In contrast to silver(I)-and copper(I)-mediated decarboxylations, the resulting aryl-gold(I) complexes are stable towards protodemetallation and can be readily isolated.

Transition metal-catalyzed decarboxylative cross-coupling reactions

“…As a confirmation of the above result, Larrosa et al also reported similar decarboxylative auration reactions mediated by (t-Bu) 3 PAuCl (Scheme 5) [13].…”

“…This transformation can also produce aryl halides from aromatic carboxylic acids. However, a stoichiometric amount of Au and Ag has to be used in the reaction [13].…”

Cellulose supported copper nanoparticles as a versatile and efficient catalyst for the protodecarboxylation and oxidative decarboxylation of aromatic acids under microwave heating

“…Copper has been found to be the most used one starting from the pioneering work by Shepherd [5][6][7]. Later on the use of other metals like, silver [8], mercury [9], gold [10], palladium [11], rhodium [12] etc. is also reported.…”

Simple, Efficient and Controllable Synthesis of Iodo/Di-iodoarenes via Ipsoiododecarboxylation/Consecutive Iodination Strategy

“…Moreover, compared with transition metal-catalyzed iodination reaction, regioselectivity can be easily controlled using this strategy in the absence of directing groups3637. Although several reports regarding the iododecarboxylation of aromatic carboxylic acids are available, limitations that hamper the laboratory and industrial applications of this strategy remain3839404142434445. For example, Okano reported the modified Hunsdiecker reactions mediated by mercury(II) or thallium(I) salts38.…”

“…Evidently, this multi-step method is operationally complex and has produced many side products. The gold(I)-catalyzed ipsoiododecarboxylation of aromatic carboxylic acids was reported by Larrosa41. However, the use of stoichiometric gold and silver is intolerable because of the prohibitive costs of these materials.…”