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In this study, a novel approach for the tertiary α‐alkylation of ketones using alkanes with electron‐deficient C─H bonds is presented, employing a synergistic catalytic system combining inexpensive copper salts with aminocatalysis. This methodology addresses the limitations of traditional alkylation methods, such as the need for strong metallic bases, regioselectivity issues, and the risk of over alkylation, by providing a high reactivity and chemoselectivity without the necessity for pre‐functionalized substrates. The dual catalytic strategy enables the direct functionalization of C(sp3)─H bonds, demonstrating remarkable selectivity in the presence of conventional C(sp3)─H bonds that are adjacent to heteroatoms or π systems, which are typically susceptible to single‐electron transfer processes. The findings contribute to the advancement of alkylation techniques, offering a practical and efficient route for the construction of C(sp3)─C(sp3) bonds, and paving the way for further developments in the synthesis of complex organic molecules. [ABSTRACT FROM AUTHOR]

The selective oxidation of benzylic C−H bonds is a pivotal transformation in organic synthesis. Undoubtedly, achieving efficient and highly selective aerobic oxidation of methylarenes to benzaldehydes has been highly challenging due to the propensity of benzaldehyde to undergo overoxidation under typical aerobic conditions. Herein, we propose an innovative approach to address this issue by leveraging electrocatalytic processes, facilitated by ion‐pair mediators [Ph3C]+[B(C6F5)4]−. By harnessing the power of electrochemistry, we successfully demonstrated the effectiveness of our strategy, which enables the selective oxidation of benzylic C−H bonds in benzylic molecules and toluene derivatives. Notably, our approach exhibited high efficiency, excellent selectivity, and compatibility with various functional groups, underscoring the broad applicability of our methodology. [ABSTRACT FROM AUTHOR]

This article provides an overview of photoredox-catalyzed C(sp2)–H bond functionalization reactions, which use low-energy photons to enable reactions under mild conditions. It discusses the contributions of researchers in advancing the field and explores the potential of using organic photocatalysts. The article focuses on the author's group's work in utilizing these reactions for C–H bond functionalizations, specifically in the context of enamides. The researchers explored various reactions, including the functionalization of enamide β-C(sp2)-H bonds, phosphorylation of alkenyl C(sp2)-H bonds, and bromination and alkylation of (hetero)arene C(sp2)-H bonds. These reactions have applications in the synthesis of natural products and pharmaceuticals, and further research is needed to develop new transformations and expand their applications. [Extracted from the article]

A transition metal-free dehydrative allylation of stabilized P-ylides with activated allylic alcohols has been developed. This protocol utilizes a calcium catalyst to facilitate the cleavage of C–OH bonds and enables smooth dehydrative cross-coupling with P-ylides, resulting in water as the sole by-product. Remarkably, this transformation exhibits excellent tolerance towards a diverse range of allylic alcohols and P-ylides. Furthermore, the subsequent Wittig reaction affords a wide array of highly functionalized 1,4-dienes with high yields. [ABSTRACT FROM AUTHOR]

In order to make sure that the reactions developed are truly catalyst-free in nature, it is important to take the following precautions when working on catalyst-free water-based reactions. 3 C-S Bond-Formation Reactions: Allenic Amides as the Electrophiles As mentioned earlier, click reactions involving Huisgen-type reactions have been used widely in chemical biology. However, many of the reported methods suffer from various drawbacks; these include the need to use toxic reagents/solvents, metal catalysts, or harsh reaction conditions and the poor atom-economy of the reactions. Keywords: catalyst-free reaction; biocompatibility; Mukaiyama aldol reaction; allenic amides; antibody-drug conjugates; green chemistry EN catalyst-free reaction biocompatibility Mukaiyama aldol reaction allenic amides antibody-drug conjugates green chemistry 1309 1316 8 07/11/23 20230725 NES 230725 Graph 1 Introduction The development of catalyst-free reactions that can work under biocompatible reaction conditions (aqueous media, pH 7.0, rt, etc.) is one of the most important goals in green chemistry and chemical biology. [Extracted from the article]