Oxone–acetone mediated Wacker-type oxidation of benzo-fused olefins

Herein we disclose a novel application of the oxone–acetone combination for the Wacker-type oxidation of indenes and dihydronaphthalenes leading, respectively, to indan-2-ones and 2-tetralones. The amount of the base employed in the reaction seems to switch the reaction path from dioxygenation to Wacker-type oxidation. Control experiments suggest that the reaction is not proceeding via the epoxide route and also that there is no role of trace amounts of metals present in the reagents on the current oxidation

Oxone–acetone mediated syn-dioxygenation of benzo-fused olefins

The oxone–acetone combination well established for olefin epoxidation has been demonstrated to be a practical reagent for the syn-dioxygenation (resulting in 1,3-dioxolanes) of indenes and dihydronaphthalenes

Ir(III)-catalyzed synthesis of isoquinoline N-oxides from aryloxime and α-diazocarbonyl compounds

An efficient Ir(III)-catalyzed C-H activation and annulations of aryloxime with α-diazocarbonyl compounds has been developed for the synthesis of substituted isoquinoline N-oxides. The reaction proceeds under mild atmospheric conditions, without any external oxidants and releases N<SUB>2</SUB> and H<SUB>2</SUB>O as the byproducts. In addition, synthetic applications of the N-oxide products have been established by performing further functionalization. An interesting dimeric iridacyclic complex allied through a bis-silver carboxylate bridge has been isolated that efficiently catalyzed the reaction

Tuning the Latency by Anionic Ligand Exchange in Ruthenium Benzylidene Phosphite Complexes

Recently discovered cis-dichloro benzylidene phosphite complexes are latent catalysts at room temperature and exhibit exceptional thermal and photochemical activation behavior in olefin metathesis reactions. Most importantly, the study of these catalysts has allowed their introduction in efficient 3-D printing applications of ring-opening metathesis derived polymers and the control of chromatically orthogonal chemical processes. Moreover, their combination with plasmonic Au-nanoparticles has given rise to novel smart materials that are responsive to light. Given the importance of the ligand shell in the initiation and reactivity behavior of this family of complexes, we set out to investigate the effect of anionic ligand exchange. Thus, we report herein two new ruthenium benzylidene benzylphosphite complexes where the chloride anionic ligands have been replaced by bromide and iodide anions (cis-Ru-Phos-Br2 & cis-Ru-Phos-I2). The thermal and photochemical activations of these dormant catalysts in a variety of ring-closing and ring-opening metathesis polymerization (RCM and ROMP) reactions were thoroughly studied and compared with the previously known chloride precatalyst. Photochemical RCM studies provided similar results, especially in non-hindered reactions, with the UV-A wavelength being the best in all cases. On the other hand, the thermal activation profile exposed that the anionic ligand significantly affects reactivity. Notably, cis-Ru-Phos-I2 disclosed particularly impressive initiation efficiency compared to the other members of the family

Ir(III)-Catalyzed Synthesis of Isoquinoline <i>N</i>‑Oxides from Aryloxime and α‑Diazocarbonyl Compounds

An efficient Ir­(III)-catalyzed C–H activation and annulations of aryloxime with α-diazocarbonyl compounds has been developed for the synthesis of substituted isoquinoline <i>N</i>-oxides. The reaction proceeds under mild atmospheric conditions, without any external oxidants and releases N₂ and H₂O as the byproducts. In addition, synthetic applications of the <i>N</i>-oxide products have been established by performing further functionalization. An interesting dimeric iridacyclic complex allied through a bis-silver carboxylate bridge has been isolated that efficiently catalyzed the reaction

Ir(III)-Catalyzed Carbenoid Functionalization of Benzamides: Synthesis of <i>N</i>‑Methoxy­isoquinoline­diones and <i>N</i>‑Methoxy­isoquinolinones

A mild and efficient Ir­(III)-catalyzed C–H carbenoid functionalization strategy has been developed to access <i>N</i>-methoxyiso­quinolinediones and <i>N</i>-methoxy­isoquinolinones. The reaction proceeds efficiently in high yield at room temperature over a broad range of substrates without requirement of any additional oxidants or a base

Fluoride-Mediated Dephosphonylation of α‑Diazo-β-carbonyl Phosphonates

The possibility of fluoride-mediated selective dephosphonylation of α-diazo-β-carbonyl phosphonates such as the Ohira–Bestmann reagent has been proposed and executed. The resulting α-diazocarbonyl intermediates undergo a (3 + 2)-cycloaddition at room temperature with conjugated olefins and benzynes. Interestingly, under the current conditions, the resulting cycloaddition products underwent either <i>N</i>-acylation (with excess α-diazo-β-carbonyl phosphonates) or Michael addition (with conjugated olefins)

Fluoride-Mediated Dephosphonylation of α‑Diazo-β-carbonyl Phosphonates

The possibility of fluoride-mediated selective dephosphonylation of α-diazo-β-carbonyl phosphonates such as the Ohira–Bestmann reagent has been proposed and executed. The resulting α-diazocarbonyl intermediates undergo a (3 + 2)-cycloaddition at room temperature with conjugated olefins and benzynes. Interestingly, under the current conditions, the resulting cycloaddition products underwent either <i>N</i>-acylation (with excess α-diazo-β-carbonyl phosphonates) or Michael addition (with conjugated olefins)

Photoelectrochemical alcohols oxidation over polymeric carbon nitride photoanodes with simultaneous H2 production

The photoelectrochemical oxidation of organic molecules into valuable chemicals is a promising technology, but its development is hampered by the poor stability of photoanodic materials in aqueous solutions, low faradaic efficiency, low product selectivity, and a narrow working pH range. Here, we demonstrate the synthesis of value-added aldehydes and carboxylic acids with clean hydrogen (H) production in water using a photoelectrochemical cell based solely on polymeric carbon nitride (CN) as the photoanode. Isotope labeling measurements and DFT calculations reveal a preferential adsorption of benzyl alcohol and molecular oxygen to the CN layer, enabling fast proton abstraction and oxygen reduction, which leads to the synthesis of an aldehyde at the first step. Further oxidation affords the corresponding acid. The CN photoanode exhibits excellent stability (>40 h) and activity for the oxidation of a wide range of substituted benzyl alcohols with high yield, selectivity (up to 99%), and faradaic efficiency (>90%).This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No. [849068]). This work was also partially supported by the joint Israel Science Foundation–National Science Foundation of China (ISF–NSFC), grant No. 2969/19, the ISF grant No.601/21, and by the Pazy Foundation (grant No. 119-2020). J.A. and H.G. gratefully acknowledge financial support by the Spanish Ministry of Science and Innovation (RTI2018-98237-CO2-1) and Generalitat Valenciana (Prometeo 2021/038). The authors thank Liel Abisdris, Jonathan Tzadikov, Ayelet Tashakory, and Rotem Geva for help with material characterization. We thank Dr Chabanne for fruitful discussion