Imine as a linchpin approach for meta-C–H functionalization
Sukdev Bag,Sadhan Jana,Sukumar Pradhan,Suman Bhowmick,Nupur Goswami,Soumya Kumar Sinha,Debabrata Maiti +6 more
TLDR
A temporary directing group (TDG) is introduced for selective meta -C–H functionalization of 2-arylbenzaldehydes via reversible imine formation and application for streamlining the synthesis of complex organic molecules without any necessary pre-functionalization at the meta position is explored.Abstract:
Despite the widespread applications of C–H functionalization, controlling site selectivity remains a significant challenge. Covalently attached directing groups (DGs) served as ancillary ligands to ensure ortho-, meta- and para-C–H functionalization over the last two decades. These covalently linked DGs necessitate two extra steps for a single C–H functionalization: introduction of DG prior to C–H activation and removal of DG post-functionalization. Here we report a temporary directing group (TDG) for meta-C–H functionalization via reversible imine formation. By overruling facile ortho-C–H bond activation by imine-N atom, a suitably designed pyrimidine-based TDG successfully delivered selective meta-C–C bond formation. Application of this temporary directing group strategy for streamlining the synthesis of complex organic molecules without any necessary pre-functionalization at the meta position has been explored. Site-selective C–H functionalization still faces some challenges, such as the introduction and removal of an appropriate directing group. Here, the authors introduce a temporary directing group for selective meta-C–H functionalization of 2-arylbenzaldehydes via reversible imine formation.read more
Citations
More filters
Journal ArticleDOI
Arene diversification through distal C(sp2)-H functionalization.
TL;DR: In this article, the authors summarize the recent elegant discoveries exploiting directing group assistance, transient mediators or traceless directors, noncovalent interactions, and catalyst and/or ligand selection to control distal C-H activation.
Site-Selective C−H Arylation of Primary Aliphatic Amines Enabled by a Catalytic Transient Directing Group
Yongbing Liu,Haibo Ge +1 more
TL;DR: In this article, a palladium-catalysed γ-arylation of primary alkylamines is achieved using an inexpensive, catalytic and transient directing group, which can be used to accelerate the transition-metal-catalyzed direct C(sp3)−H functionalization.
Journal ArticleDOI
Organocatalytic Enantioselective Synthesis of Axially Chiral Molecules: Development of Strategies and Skeletons.
TL;DR: In this paper , the intrinsic nucleophilicity of aromatic amines and alcohols was modulated by an electron-withdrawing activating group which could associate with the catalyst for reactivity enhancement and selectivity control.
Journal ArticleDOI
Weak bonding strategies for achieving regio- and site-selective transformations
TL;DR: In this article , the authors summarize the advances that have been made during the past two decades, highlighting their relative simplicity in promoting regio- and site-selective reactions that would otherwise be difficult to perform on molecules.
Journal ArticleDOI
Emergence of Pyrimidine-Based meta-Directing Group: Journey from Weak to Strong Coordination in Diversifying meta-C-H Functionalization.
Uttam Dutta,Debabrata Maiti +1 more
TL;DR: This Account describes the journey from the weakly coordinating cyano-based DGs to the strongly coordinating pyrimidine-based DG to achieve diverse meta-C-H functionalization of electronically and sterically unbiased arenes and the design of an elegant "U-shaped" template for the first time is devised.
References
More filters
Journal ArticleDOI
C-H bond activation enables the rapid construction and late-stage diversification of functional molecules
TL;DR: This Perspective highlights the potential of metal-catalysed C-H bond activation reactions, which now extend beyond the field of traditional synthetic organic chemistry, and are more atom- and step-economical than previous methods.
Journal ArticleDOI
Catalytic functionalization of arenes and alkanes via C-H bond activation.
TL;DR: Several novel synthetic reactions of arenes and alkanes discovered and investigated in the laboratory are summarized here.
Journal ArticleDOI
Efficient catalytic addition of aromatic carbon-hydrogen bonds to olefins
Shinji Murai,Fumitoshi Kakiuchi,S. Sekine,Yasuo Tanaka,Asayuki Kamatani,Motohiro Sonoda,Naoto Chatani +6 more
TL;DR: The selective cleavage of carbon-hydrogen bonds in organic compounds is a critical step in many organic syntheses, and is particularly important in the conversion of hydrocarbons to useful organic compounds.
Journal ArticleDOI
Remarkably Selective Iridium Catalysts for the Elaboration of Aromatic C-H Bonds
TL;DR: A family of Ir catalysts now enables the direct synthesis of arylboron compounds from aromatic hydrocarbons and boranes under “solventless” conditions because they are highly selective for C–H activation and do not interfere with subsequent in situ transformations, including Pd-mediated cross-couplings with aryL halides.
Journal ArticleDOI
A Meta-Selective Copper-Catalyzed C–H Bond Arylation
TL;DR: A copper-catalyzed arylation reaction is developed that selectively substitutes phenyl electrophiles at the aromatic carbon–hydrogen sites meta to an amido substituent and is applicable to a broad range of aromatic compounds.