Photoinduced Regioselective Olefination of Arenes at Proximal and Distal Sites.

The Fujiwara-Moritani reaction has had a profound contribution in the emergence of contemporary C-H activation protocols. Despite the applicability of the traditional approach in different fields, the associated reactivity and regioselectivity issues had rendered it redundant. The revival of this exemplary reaction requires the development of a mechanistic paradigm that would have simultaneous control on both the reactivity and regioselectivity.

Ligand-Enabled δ-C(sp )-H Borylation of Aliphatic Amines.

Directed C-H functionalization has been realized as a complimentary technique to achieve borylation at a distal position of aliphatic amines. Here, we demonstrated the oxidative borylation at the distal δ-position of aliphatic amines using various borylating agents, a palladium catalyst, and a rightly tuned ligand in the presence of a cheap oxidant. Moreover, an organopalladium δ-C(sp )-H-activated intermediate has been isolated and crystallographically characterized to get mechanistic insight.

A direct route to six and seven membered lactones γ-C(sp)-H activation: a simple protocol to build molecular complexity.

Lactones comprise a class of valuable compounds having biological as well as industrial importance. Development of a methodology to synthesize such molecules directly from readily available materials such as aliphatic carboxylic acid is highly desirable. Herein, we have reported synthesis of δ-lactones and ε-lactones selective γ-C(sp)-H activation.

Ultrasound-Facilitated Direct meta-C-H Functionalization of Arenes: A Time-Economical Strategy under Ambient Temperature with Improved Yield and Selectivity.

The horizon of ultrasound-assistance has been expanded to palladium-catalyzed distal C-H functionalization of arenes. Compared to thermal conditions, operationally simple ultrasound mediated distal C-H functionalization occurred with a shorter reaction time and enhanced reactivity of reactants to give superior yields with improved selectivity both in terms of meta:others and mono:di. A wide variety of meta-functionalizations such as olefination, alkylation, acetoxylation, allylation and cyanation were successfully carried out under ambient temperature.

Ligand-Enabled Pd -Catalyzed Iterative γ-C(sp3)-H Arylation of Free Aliphatic Acid.

C-H functionalization of aliphatic carboxylic acids without attaching exogenous auxiliary has been so far limited at the proximal β-position. In this work, we demonstrate a ligand enabled palladium catalyzed first regioselective distal γ-C(sp3)-H functionalization of aliphatic carboxylic acids without incorporating an exogenous directing group. Aryl iodides containing versatile functional groups including complex organic molecules are well tolerated with good to excellent yields during the γ-C(sp3)-H arylation reaction.

Photocatalyzed borylation using water-soluble quantum dots.

The synthesis of arylboronates by Sandmeyer-type reactions in the presence of water still remains a significant challenge. Herein, we report the use of water-soluble MPA-capped quantum dot (QD) photocatalysts for the borylation of diazonium salts in the presence of water. A biphasic system under mild acidic conditions remains critical to prevent decomposition and competitive disulphide bond formation.

Iterative Arylation of Amino Acids and Aliphatic Amines via δ-C(sp )-H Activation: Experimental and Computational Exploration.

Directed C-H functionalization has been realized as a complementary tool to the traditional approaches for a straightforward access of non-proteinogenic amino acids; albeit such a process is restricted mostly up to the γ-position. In the present work, we demonstrate the diverse (hetero)arylation of amino acids and analogous aliphatic amines selectively at the remote δ-position by tuning the reactivity controlled by ligands. An organopalladium δ-C(sp )-H activated intermediate has been isolated and crystallographically characterized.