Modular Synthesis of ortho-Thiolated Aryl Esters Enabled with Thiocarbonate through Catellani Strategy

Herein, we report a palladium/norbornene/copper co-catalyzed single-step approach that merges selective ortho C−H bond esterification with ipso thiolation for construction of synthetically versatile 2-arylthio aryl esters under exceptionally mild conditions. Importantly, this process proceeded in a highly efficient manner, allowing alkoxycarbonyl and thio groups to be installed into one aryl iodides simultaneously by harnessing thiocarbonate as bifunctional reagent. The method has been demonstrated to accommodate good functionalities and features broad substrate scope.     

Amidyl Radical Directed γ-C(sp3)−H Functionalization with Silyl Enol Ethers via Photoredox Catalysis

Herein we reported an efficient photoredox-catalyzed reaction for site-selective C(sp³)−H functionalization of carboxamides with silyl enol ethers as radical acceptors. The reaction proceeded through amidyl radical-directed 1,5-hydrogen atom transfer (1,5-HAT) and C(sp³)−C(sp³) bond formation via radical addition of silyl enol ethers. The process features mild conditions and high functional-group tolerance, allowing the preparation of a series of carboxamides with pendant carbonyl moieties.     

Visible-Light-Mediated Self-Sensitized Oxidative and Regioselective C(sp2)−H Selenylation and Sulfenylation of Substituted 2-Amino-1,4-Naphthoquinones

A photochemical method based on visible-light (white LEDs/sunlight) irradiation has been developed for the regioselective and oxidative C(sp²)−H selenylation and sulfenylation of substituted 2-amino-1,4-naphthoquinones under oxygen atmosphere. The photochemical process does not require any external photoredox catalysts. The other notable advantages of this protocol are metal-free synthesis, visible light/sunlight as energy sources, good substrate scope, and moderate to good yields (41–91 %) with high regioselectivity.     

Ring-polymer Molecular Dynamics Simulation for the Adsorption of H2 on Ice Clusters (H2O)n (n=8, 10, and 12)

In the interstellar medium, the H₂ adsorption and desorption on the solid water ice are crucial for chemical and physical processes. We have recently investigated the probabilities of H₂ sticking on the (H₂O)₈ ice, which has quadrilateral surfaces. We have extended the previous work using classical MD and ring-polymer molecular dynamics (RPMD) simulations to the larger ice clusters, (H₂O)₁₀ and (H₂O)₁₂, which have pentagonal and hexagonal surfaces, respectively. The H₂ sticking probabilities decreased as the temperature increased for both cluster cases, whereas the cluster-size-independent profiles were observed. It is thought that the size independence of the probabilities is qualitatively understood from the similar binding energies for all the three cluster systems. Furthermore, the RPMD sticking probabilities are smaller than the classical ones because of the reduction in the binding energies owing to nuclear quantum effects, such as vibrational quantization.     

Iron‐Catalyzed C(sp2)H and C(sp3)H Methylations of Amides and Anilides

The so‐called magic methyl effect significantly boosts the bioactivities and physical properties of pharmacologically active drugs. Direct introduction of the methyl group by C?H activation was accomplished with a versatile iron catalyst, which enabled the C?H methylation of (hetero)benzamides, anilides, alkenes, and even alkanes by triazole assistance in a chemo‐, site‐ and diastereo‐selective fashion.     

Cationic Cobalt(III)‐Catalyzed Aryl and Alkenyl CH Amidation: A Mild Protocol for the Modification of Purine Derivatives

A cationic cobalt(III)‐catalyzed direct C?H amidation of unactivated (hetero)arenes and alkenes by using 1,4,2‐dioxazol‐5‐ones as the amidating reagent has been developed. This transformation proceeds efficiently under external oxidant‐free conditions with a broad substrate scope. Moreover, 6‐arylpurine compounds, which often exhibit high potency in antimycobacterial, cytostatic, and anti‐HCV activities, can be smoothly amidated, thus offering a mild protocol for their late stage functionalization.     

Condensed‐Phase,Halogen‐Bonded CF3I and C2F5I Adducts for Perfluoroalkylation Reactions

A family of practical, liquid trifluoromethylation and pentafluoroethylation reagents is described. We show how halogen bonding can be used to obtain easily handled liquid reagents from gaseous CF₃I and CF₃CF₂I. The synthetic utility of the new reagents is exemplified by a novel direct arene trifluoromethylation reaction as well as adaptations of other perfluoroalkylation reactions.     

Hydrothermal Syntheses and Crystal Structures of Two Complexes of Cobalt and Manganese Assembled by 4,4'-Oxydibenzoic Acid

Two new coordination polymers [Co(oba)(mbix)]2n·n H2O(1) and [Mn(Hoba)2(H2O)2]n(2)(H2oba = 4,4'-oxydibenzoic acid, mbix = 1,3-bis(imidazol-1-ylmethyl)benzene) have been successfully synthesized under hydrothermal conditions. Their structures have been determined by elemental analyses, IR spectroscopy, UV and single-crystal X-ray diffraction analysis. The intermolecular hydrogen bonding and π-π stacking interactions extend the complexes into a 3D supramolecular structure.     

Dioxygen‐Mediated Decarbonylative CH Alkylation of Heteroaromatic Bases with Aldehydes

An operationally simple and economical method for the direct alkylation of heteroaromatic bases employing readily available aldehydes as alkyl radical precursors and molecular oxygen as a reagent is presented. This simple transformation demonstrates a broad substrate scope with respect to aldehydes and nitrogen heterocycles, enabling the introduction of several medicinally important yet challenging alkyl moieties, such as ethyl, isopropyl, tert‐butyl, and cyclohexyl to the different classes of heterocyclic bases in good to excellent yields.     

A General and Scalable Synthesis of Aeruginosin Marine Natural Products Based on Two Strategic C(sp3)H Activation Reactions

An efficient and scalable access to the aeruginosin family of marine natural products, which exhibit potent inhibitory activity against serine proteases, is reported. This synthesis was enabled by the strategic use of two different, recently implemented C(sp³)? H activation reactions. The first method led to the common 2‐carboxy‐6‐hydroxyoctahydroindole (Choi) core of the target molecules on a large scale, whereas the second one provided rapid and divergent access to the various hydroxyphenyllactic (Hpla) subunits. This strategy allowed the synthesis of the aeruginosins 98B and 298A, with the latter being obtained in unprecedentedly large quantities.