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A useful protocol for achieving decarboxylative cross-coupling (DCC) of redox-active esters (RAE, isolated or generated in situ) and halo­(hetero)­arenes is reported. This pragmatically focused study employs a unique Ag–Ni electrocatalytic platform to overcome numerous limitations that have plagued this strategically powerful transformation. In its optimized form, coupling partners can be combined in a surprisingly simple way: open to the air, using technical-grade solvents, an inexpensive ligand and Ni source, and substoichiometric AgNO3, proceeding at room temperature with a simple commercial potentiostat. Most importantly, all of the results are placed into context by benchmarking with state-of-the-art methods. Applications are presented that simplify synthesis and rapidly enable access to challenging chemical space. Finally, adaptation to multiple scale regimes, ranging from parallel milligram-based synthesis to decagram recirculating flow is presented.

A user-friendly approach is presented to sidestep the venerable Grignard addition to unactivated ketones to access tertiary alcohols by reversing the polarity of the disconnection. In this work a ketone instead acts as a nucleophile when adding to simple unactivated olefins to accomplish the same overall transformation. The scope of this coupling is broad as enabled using an electrochemical approach, and the reaction is scalable, chemoselective, and requires no precaution to exclude air or water. Multiple applications demonstrate the simplifying nature of the reaction on multistep synthesis, and mechanistic studies point to an intuitive mechanism reminiscent of other chemical reductants such as SmI 2 (which cannot accomplish the same reaction).

There is a strong parallel between simple alcohol oxidation and carbonyl desaturation from both strategic and tactical vantage points. As they both seek to extract hydrogen from an organic substrate, they are deceptively simple looking transformations that have been addressed over the past 70+ years through stoichiometric means. The past decade has seen an intensifying level of interest in rendering both of these simple reactions catalytic. In this Perspective, recent advances from the past 5 years are highlighted featuring both transition-metal-catalyzed and metal-free approaches to carbonyl desaturation. Through a historical overview and a detailed look at each of these new developments, we seek to address the question of in what context a catalytic strategy emerges as ideal.

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