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The reliance on wasteful stoichiometric reagents to accomplish dehydration reactions such as esterification, amidation, and alcohol substitution is a longstanding challenge in synthetic chemistry. To address this problem, an electrochemical approach has been developed as a new conceptual platform for dehydration reactions. As a proof-of-concept demonstration, an electrochemical esterification protocol has been described that proceeds at room temperature, without acid or base additives, and without consuming stoichiometric reagents. This approach therefore overcomes key complications of esterification chemistry, and we envision that it will similarly enable improvements to a range of important, related transformations. 1 Introduction 2 An Electrochemical Design for Catalytic Dehydration 3 Electrochemical Esterification 4 Conclusions [ABSTRACT FROM AUTHOR]

A modified palladium on carbon (Pd/C) catalyzed hydrogenolysis method for the removal of the phenolic-OH group in phenolic alkaloids as the 1-phenyl-1H-tetrazol-5-yl derivative by the addition of magnesium metal or ammonium acetate in acetic acid is described. Five different types of isoquinoline alkaloids, i.e., phenanthrene alkaloid, aporphine, pavine, protoberberine, and 1-benzyltetrahydroisoquinoline, were used as reactants. The results indicate that the addition of either magnesium metal or ammonium acetate has the advantage of decreasing the amount of Pd/C and the accelerating reaction rate over the simple Pd/C-catalyzed hydrogenolysis, thus it is practical for largerscale preparation of de-phenolated alkaloids for pharmacological study. [ABSTRACT FROM AUTHOR]

The cyclopropenone catalyzed nucleophilic substitution of alcohols by methanesulfonate ion with inversion of configuration is described. This work provides an alternative to the Mitsunobu reaction that avoids the use of azodicarboxylates and generation of hydrazine and phosphine oxide byproducts. This transformation is shown to be compatible with a range of functionality. A cyclopropenone scavenge strategy is demonstrated to aid purification. [ABSTRACT FROM AUTHOR]

A free-radical approach has enabled the development of a synthetically versatile alkyl-(hetero)arylation of olefins. Alkyl and (hetero)aryl groups were added concurrently to a full suite of mono- to tetrasubstituted simple alkenes ( i.e. , without requiring directing or electronically activating groups) for the first time. Key advances also included the introduction of synthetically diversifiable alkyl groups featuring different degrees of substitution, good diastereocontrol in both cyclic and acyclic settings, the addition of biologically valuable heteroarenes featuring Lewis basic nitrogen atoms as well as simple benzenes, and the generation of either tertiary or quaternary benzylic centers. The synthetic potential of this transformation was demonstrated by leveraging it as the key step in a concise synthesis of oliceridine, a new painkiller that received FDA approval in 2020., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)