Visible light promoted cross-dehydrogenative coupling reaction has been emerged as an excellent strategy for the direct formation of C-C/C-heteroatom bonds from simple compounds. Use of renewable energy resources and inessential...

Transition metals have been an indispensable component of modern catalysis and among these palladium is the top‐ranked choice of chemists as a catalyst. After the several important developments of palladium catalysed C−C cross‐coupling reactions, carbonylative transformations have been realised as an attractive post modification of these reactions. Carbonylative Suzuki‐Miyaura coupling reaction is among such transformations for direct incorporation of CO fragment for the preparation of biaryl or aryl/alkyl ketones via transition‐metal catalysis. Ketone functionality is basically a valuable building block having huge pharmaceutical and agrochemical applications. Moreover, carbonylative Suzuki‐Miyaura coupling is also used in the synthesis of various natural bioactive molecules through the direct joining of molecular fragments via CO bridge. In this review, the past decade developments in the carbonylative Suzuki‐Miyaura coupling reactions are documented in detail with modern approaches in transition‐metal catalysis.

An oxidant, base and metal free methodology has been developed for the synthesis of various 2-substituted and non-substituted benzazoles, quinazolines and quinazolinones using oxalic/malonic acids as an in situ carbon source. This methodology is applicable for a wide range of substituted o-phenylenediamine, o-aminothiophenol, o-aminophenol and o-aminobenzamide containing various functional groups and provides good to excellent yields of the corresponding product. Furthermore an easy workup procedure, high yield and easy isolation of products are key features of this methodology. The developed protocol is also applicable for the gram scale synthesis of benzimidazoles.

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A very unusual role of polystyrene stabilized rhodium (Rh@PS) nanoparticles as a supported catalyst is described for “reverse-esterification” of ethanol with benzyl/alkyl alcohols or aldehydes.

A highly efficient hypervalent iodine‐promoted regiocontrolled ring contractive cyanation (RCC) reaction of exocyclic β‐enaminones for the synthesis of cyanocyclopentanone (CCP) was demonstrated at ambient temperature with a wide substrate scope. The methodology offers a facile technique to construct an amino carbonitrile‐containing quaternary stereocenter at the α‐position of cyclopentanone in good yields. The sequence of substrate addition that can facilitate the reaction to follow different pathways (free radical/non‐radical) to afford the same final product was critically investigated.magnified image

Scheme1.Comparisono f[ 2 + +2+ +1] type carbonylative cyclizations of alkynes and alkenes.

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