A methyl phenyl sulfoximine (MPS) is used as a directing group in the ruthenium‐catalyzed intramolecular hydroarylation of alkene‐tethered benzoic acid derivatives to afford dihydrobenzofurans and ...indolines in good to excellent yields. A one‐pot, unsymmetrical, twofold C−H functionalization involving intramolecular C−C and intermolecular C−C/C−N bond formations is successfully demonstrated by using a single set of catalytic reaction conditions, which is unprecedented thus far. A novel isoquinolone‐bearing dihydrobenzofuran is constructed through an unsymmetrical twofold C−H functionalization.
In a single shot: A methyl phenyl sulfoximine (MPS) is used as a directing group in the ruthenium‐catalyzed intramolecular hydroarylation of alkene‐tethered benzoic acid derivatives to afford dihydrobenzofurans and indolines in excellent yields. A one‐pot, unsymmetrical, twofold C−H functionalization involving intramolecular C−C and intermolecular C−C/C−N bond formations is successfully demonstrated.
An operationally simple electrochemical method for the transition‐metal‐free ipso‐thiocyanation of arylboronic acids and aryl trifluoroborates has been developed. The SCN electrophile is generated in ...situ by anodic oxidation of thiocyanate anions, which avoids formation of salt waste and prevents unwanted side reactions arising from chemical oxidants. The reaction proceeds regiospecifically, and the scope extends to non‐activated aromatic systems.
The Ru(II)-catalyzed intermolecular o-C-H amidation of arenes in N-benzoylated sulfoximine with sulfonyl azides is demonstrated. The reaction proceeds with broad substrate scope and tolerates various ...functional groups. Base hydrolysis of the amidation product provides the anthranilic acid derivatives and methylphenyl sulfoximine (MPS) directing group. This method is successfully employed for the synthesis of HMR 1766.
Sulfoximines direct: A new protocol for the chemo‐ and regioselective ortho CH acetoxylation of arenes in N‐benzoylated sulfoximines is reported. The sulfoximine directing group is easily detached ...from the CH oxidation product through acid‐promoted hydrolysis, isolated, and reused (see scheme). The meta‐substituted phenols are synthesized following this strategy and the stereointegrity of the sulfoximine is preserved in this transformation. C(sp3)H acetoxylation of the methyl group is also demonstrated.
The reusable sulfoximine directing-group-assisted Ru(II)-catalyzed chemo- and regioselective ortho-C-H alkenylation of arenes and heteroarenes with acrylates and α,β-unsaturated ketones/vinyl sulfone ...is shown. The N-aroyl sulfoximine undergoes annulation with diphenylacetylene, delivering isoquinolinones and methyl phenyl sulfoxide. The present protocol is successfully employed for the synthesis of the EP3 receptor antagonist analogue.
A straightforward method for the electrochemical C−H cyanation of arenes and heteroarenes that proceeds at room temperature in MeOH, with NaCN as the reagent in a simple, open, undivided ...electrochemical cell is reported. The platinum electrodes are passivated by adsorbed cyanide, which allows conversion of an exceptionally broad range of electron‐rich substrates all the way down to dialkyl arenes. The cyanide electrolyte can be replenished with HCN, opening opportunities for salt‐free industrial C−H cyanation.
Aromatic substitution: The electrochemical C−H cyanation of arenes is shown to constitute an advantageous synthetic alternative to traditional, waste‐intensive cyanation methods. It gives high yields by using simple, undivided electrochemical cells equipped with platinum‐sheet electrodes, proceeds well even in the presence of air and moisture, and allows waste‐free regeneration of the electrolyte (see scheme).
Direct difunctionalization of chemically distinct ortho - and peri -C–H bonds of fused hetero(arenes) is illustrated through an unusual one-pot domino {4 + 2 & 5 + 2} double annulation with alkynes ...for the first time. This process is viable under Ru( ii )-catalysis using a sulfoximine directing group and builds four bonds (C–C)–(C–N) and (C–C)–(C–O) in a single operation. Such synthetic manifestation offers access to uncommon 6,7-fused oxepino-pyridine skeletons. DFT calculations provide mechanistic insight into this double annulation of naphthoic acid derivatives with alkynes and corroborate the participation of a ruthena-oxabicyclooctene intermediate, which is responsible for the rare 7-membered ring formation.
Ru(II)-catalyzed intermolecular ortho-C-H amidation of weakly coordinating aromatic ketones with sulfonyl azides is reported. The developed reaction protocol can be extended to various substituted ...aromatic ketones to afford a wide range of desired C-N bond formation products in good yields.
This review highlights the importance of removable and reusable directing groups in C−H activation. The functionalization of unactivated sp2 C−H bonds assisted by removable directing groups is ...highlighted and summarized.
Remove, reuse, recycle: This review highlights the importance of removable and reusable directing groups in C−H activation. The functionalization of unactivated sp2 C−H bonds assisted by removable directing groups is highlighted and summarized.
Multiple C−H bond functionalizations promptly install diverse groups on the molecular framework and consequently fabricate complex molecular entities. This review briefly surveys the conceptual ...development of directing group assisted unsymmetrical multiple functionalization of arene C(sp2)−H bonds, which is exceedingly appealing and highly important.
This review briefly summarizes a systematic development of directing group assisted unsymmetrical multiple functionalization of arene C(sp2)−H bonds. The domino multiple C−H functionalization gives a straightforward access to complex molecular architecture.
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