Debabrata Maiti 교수

Transition-metal-catalyzed C-H activation has developed a contemporary approach to the omnipresent area of retrosynthetic disconnection. Scientific researchers have been tempted to take the help of this methodology to plan their synthetic discourses. This paradigm shift has helped in the development of industrial units as well, making the synthesis of natural products and pharmaceutical drugs step-economical. In the vast zone of C-H bond activation, the functionalization of proximal C-H bonds ha

Transition metal-catalyzed aryl C-H activation is a powerful synthetic tool as it offers step and atom-economical routes to site-selective functionalization. Compared with proximal <i>ortho</i>-C-H activation, distal (<i>meta</i>- and/or <i>para</i>-) C-H activation remains more challenging due to the inaccessibility of these sites in the formation of energetically favorable organometallic pretransition states. Directing the catalyst toward the distal C-H bonds requires judicious template engine

C-C bond forming reactions incarnate the core of organic synthesis because of their fundamental applications to molecular diversity and complexity. In recent years, use of carboxylic acid as one of the coupling partners in place of conventional organometallic reagents has seen an upsurge due to its potency to generate similar organometallic intermediates after decarboxylation. This Review provides an overview on the most recent progress in the field of C-C bond formation involving decarboxylatio

We report our studies on the use of two catalyst systems, based on the ligands BrettPhos (1) and RuPhos (2), which provide the widest scope for Pd-catalyzed C-N cross-coupling reactions to date. Often low catalyst loadings and short reaction times can be used with functionalized aryl and heteroaryl coupling partners. The reactions are highly robust and can be set up and performed without the use of a glovebox. These catalysts should find wide application in the synthesis of complex molecules inc

In industries and academic laboratories, several late transition metal-catalyzed prerequisite reactions are widely performed during single and multistep synthesis. However, besides the desired products, these reactions lead to the generation of numerous chemical waste materials, by-products, hazardous gases, and other poisonous materials, which are discarded in the environment. This is partly responsible for the creation of global warming, resulting in climate adversities. Thus, the development

Directing group assisted ortho-C-H activation has been known for the last few decades. In contrast, extending the same approach to achieve activation of the distal meta- and para-C-H bonds in aromatic molecules remained elusive for a long time. The main challenge is the conception of a macrocyclic transition state, which is needed to anchor the metal catalyst close to the target bond. Judicious modification of the chain length, the tether linkage, and the nature of the catalyst-coordinating dono

An economical approach to α-CF3-substituted ketones, which are important intermediates in synthetic and medicinal chemistry, employs olefins and the readily available Langlois reagent (CF3SO2Na). The reaction is operationally simple, proceeds at room temperature, and exhibits an excellent tolerance toward a wide variety of functional groups. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be r

Direct catalytic transformation of C–H bonds to new functionalities has provided a powerful strategy to synthesize complex molecular scaffolds in a straightforward way. Unstinting efforts of the synthetic community have helped to overcome the long-standing major challenge of regioselectivity by introducing the directing group concept. However, the full potential of the strategy cannot be realized unless the activated C–H bonds are stereochemically controlled. The enantioselective C–H bond functi

C-H deuteration has been intricately developed to satisfy the urgent need for site-selectively deuterated organic frameworks. Deuteration has been primarily used to study kinetic isotope effects of reactions but recently its significance in pharmaceutical chemistry has been discovered. Deuterium labelled compounds have stolen the limelight since the inception of the first FDA-approved deuterated drug, for the treatment of chorea-associated Huntington's disease, and their pharmacological importan

Among numerous solvents available for chemical transformations, 1,1,1,3,3,3-hexafluoro-2-propanol (popularly known as HFIP) has attracted enough attention of the scientific community in recent years. Several unique features of HFIP compared to its non-fluoro analogue isopropanol have helped this solvent to make a difference in various subdomains of organic chemistry. One such area is transition metal-catalyzed C-H bond functionalization reactions. While, on one side, HFIP is emerging as a green

Divinylbenzene derivatives represent an important class of molecular building blocks in organic chemistry and materials science. Reported herein is the palladium-catalyzed synthesis of divinylbenzenes by meta-C-H olefination of sulfone-based arenes. Successful sequential olefinations in a position-selective manner provided a novel route for the synthesis of hetero-dialkenylated products, which are difficult to access using conventional methods. Additionally, 1,3,5-trialkenylated compounds can be

O- or N-arylated aminophenol products constitute a common structural motif in various potentially useful therapeutic agents and/or drug candidates. We have developed a complementary set of Cu- and Pd-based catalyst systems for the selective O- and N-arylation of unprotected aminophenols using aryl halides. Selective O-arylation of 3- and 4-aminophenols is achieved with copper-catalyzed methods employing picolinic acid or CyDMEDA, trans-N,N'-dimethyl-1,2-cyclohexanediamine, respectively, as the l

Triple CH functionalization: Palladium-catalyzed synthesis of benzofurans and coumarins by reacting phenols and unactivated olefins is described. The reaction comprises sequential CH functionalization and shows diverse functional group compatibility. Preliminary mechanistic studies shed light into the possible mechanisms. As a service to our authors and readers, this journal provides supporting information supplied by the authors. Such materials are peer reviewed and may be re-organized for on

Donor makes the difference: The mononuclear η1-superoxo copper(II) complex 1 undergoes dioxygen activation with the addition of hydrogen-atom donors. Net O2-derived O-atom insertion into the N-methyl group of the ligand leads to formation of a copper(II)-alkoxide product 2. The cupric superoxo species 1 itself is not capable of the observed hydroxylation reaction. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2002/2008/z704389_s.pdf or

Various practical methods for the selective C-H functionalization of the ortho and recently also of the meta position of an arene have already been developed. Following our recent development of the directing-group-assisted para C-H functionalization of toluene derivatives, we herein report the first remote para C-H functionalization of phenol derivatives by using a recyclable silicon-containing biphenyl-based template. The effectiveness of this strategy was illustrated with different synthetic