Herein we present a Pd-catalyzed direct C−H hydroxylation of 2-arylpyridines using molecular oxygen (O 2 ) as the sole oxidant. The key aspects of the method include: (a) the activation of molecular oxygen with a nontoxic and inexpensive aldehyde; (b) an efficient association of the in situ-generated acyl peroxo radical with palladium catalysis; and (c) convenient operating conditions. On the basis of the results obtained in a series of control experiments, a Pd II /Pd IV catalytic cycle is implicated for the transformations. Furthermore, the method offers an easy access to a broad range of substituted 2-(pyridin-2-yl)phenols in good isolated yields.

Visible light has been recognized as an economical and environmentally benign source of energy that enables chemoselective molecular activation of chemical reactions and hence reveal a new horizon for the design and discovery of novel chemical transformations. On the other hand, asymmetric catalysis represents an economic method to satisfy the increasing need for enantioenriched compounds in the chemical and pharmaceutical industries. Therefore, combining visible light photocatalysis with asymmetric catalysis creates a wider range of opportunities for the development of mechanistically unique reaction schemes. However, there arise two main problems like undesirable photochemical background reactions and difficulties in controlling the stereochemistry with highly reactive photochemical intermediates which can pose a serious challenge to the development of asymmetric visible light photocatalysis. In recent years, several methods have been developed to overcome these challenges. This review summarizes the recent advances in visible light‐induced enantioselective reactions. We divide our discussion into four categories: Asymmetric photoredox organocatalysis, asymmetric transition metal photoredox catalysis, asymmetric photoredox Lewis acid catalysis and asymmetric photoinduced energy transfer catalysis. Special emphasis has been given to different catalytic activation modes that enable the construction of challenging carbon‐carbon and carbon‐heteroatom bond in an enantioselective fashion. A brief analysis of substrate scope and limitation as well as reaction mechanism of these reactions has been included.

Phenol and its derivatives are extremelyu seful compoundsi no rganic synthesis, medicinal chemistry and material sciences. The synthesis of phenols involvings elective construction of the CÀOb ond at aC ÀHb ond of arenes using transition-metalc atalysis represents the most appealing strategy.I ndeed, active research is currently going on for the synthesis of valuable phenolic compoundsu sing at ransition-metal-catalyzed CÀHf unctionalization strategy.T his short review summarizes recent advances on palladium-catalyzed CÀOb ond forming reactions that enable direct access to phenolic compounds. These catalytic reactions proceed either via CÀHe sterification with trifluoroacetic acid/trifluoroacetic anhydridef ollowedb yi ns itu hydrolysis of the ester or via direct CÀHh ydroxylation.Abrief analysis of substrate scope and limitation, reaction mechanism as well as synthetic utility of these reactions has been included.

Epidermal growth factor receptor (EGFR) is a tyrosine kinase receptor that causes different types of cancer on its overexpression or mutation and rearrangement or amplification of the EGFR gene. Inhibition...

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