Transition metal-catalyzed carbonylative coupling reaction for the synthesis of polyfunctional biaryl ketones is attracted enormous attention because their core structural scaffolds are commonly embedded in various naturally occurring molecules,

Scheme 1. Pharmaceutical and biological significance of biaryl ketones

pharmaceuticals, and agrochemical industries.^[1]Some examples of naturally occurring biaryl ketones exhibit extraordinary antitumor activity I ,^[2]photosensitizers II ,^[3] electric material precursors III ,^[4]

neoplastic agents IV ,^[5] and anticancer activity V (Scheme 1).^[6] Given the significance of biaryl ketones, considerable effort has gone into their synthesis.

Conventionally, the biaryl ketone is synthesized using Friedel-Crafts acylation of arene of acid anhydrides or aryl halides with Lewis’s acid. However, this method’s use of the excess amount of Lewis acid causes problems with various functional groups, resulting in a large amount of waste and also suffering from regioselectivity.^[7]In this regard, the transition metal-catalyzed carbonylative cross-coupling reaction is a useful and simple technique for the synthesis of polyfunctionalized biaryl ketones. Generally, transition metal-catalyzed carbonylation reactions for the synthesis of biaryl ketones can be broadly classified into three groups: a) Synthesis of biaryl ketone via carbonylative cross-coupling reaction between organic halides and nucleophilic organometallic compounds.^[8] This approach commonly allowed the synthesis of both symmetric and unsymmetric biaryl ketones. b) palladium-catalyzed homo-coupled reductive carbonylation of aryl halide in the presence of reducing agents.^[9] c) carbonylative self-coupling reaction of nucleophilic organometallic compounds under oxidizing agents.^[10]

Over the past decades, various catalytic synthetic processes have been established for the synthesis of symmetric biaryl ketones. The transition metal-catalyzed aerobic oxidation of terminal olefins to form symmetric and unsymmetric carbonyl compounds. The oxidative self-coupling of aryl aldehydes via decarbonylation forms biaryl ketones and biaryls (Scheme 1a, 1b).^[11] Although these transformations make an important contribution to biaryl ketones synthesis, it suffers from the usage of moisture-sensitive ligands, harsh reaction conditions, limited substrate scope, and longer reaction time. Recently, several new synthetic approaches have been developed by chemists to reduce these types of problems. The transition metal-catalyzed carbonylative self-coupling reaction is the most effective approach for transforming different functionalized ketones.

Recently, Wu and co-workers reported Bismuth-mediated synthesis of symmetric biaryl ketone by oxidative carbonylation of triarylbismuthings using m-CPBA (3-chloroperoxybenzoic acid) as an oxidant in chloroform under high CO pressure (40 bar) (Scheme 1c).^[12]