Recent Advances in Catalytic Carbonylation Reactions in Alternative Reaction Media

Since the discovery of the hydroformylation (oxo-synthesis or Roelen reaction) and the Reppe-reaction, the transition metal-catalyzed carbonylation reactions, providing versatile, facile, and even atom-economic methods for the selective incorporation of C=O functionality to various skeletons, have gained tremendous importance in synthetic organic chemistry from laboratories to industrial applications. The carbonylation of carbon-carbon multiple bonds, aromatic halides, triflates, etc., in the presence of various nucleophiles has led the way to produce aldehydes, carboxylic acids, esters, amides, etc., in the fine chemical industry. However, these protocols usually proceed in conventional, fossil-based, and usually toxic reaction environments. Thus, several attempts have been directed to developing efficient carbonylation methods in alternative, less harmful, non-fossil-based and even in renewable reaction media. In this review, we overview the recent applications of alternative solvents such as water, biomass-based alcohols, gamma-valerolactone (GVL), 2-methyltetrahydrofuran (2-MeTHF), ionic liquids (ILs), deep eutectic solvents (DES), alkyl levulinates, limonene, alpha-pinene, and dimethyl carbonate as well as fluorous media to improve efficiency, safety and environmentally benign nature of carbonylation protocols.