Green Oxidation of Isochromans to Isochromanones with Molecular Oxygen Catalyzed by a Tetranuclear Vanadium Cluster

Abstract

Comprehensive Summary Isochromanone is the core structure of many bioactive compounds. Direct oxidation of isochromans is one of leading methods for the construction of isochromanones, while most established processes remain suffering from the use of environmentally unfriendly metal oxidants, harsh reaction conditions, and the difficulty in catalyst recycling and product separation. Herein, we report a convenient, cost‐effective, and green method for the synthesis of high‐value added isochromanones via isochroman oxidations with O2 by a novel heterogeneous vanadium cluster catalyst (Cat.1) under mild conditions. This reaction protocol demonstrates high catalytic activity with good catalyst recyclability and reusability for a wide scope of substrates.

An artificial enzyme of a polyoxometalate-supported cobalt complex for the oxidation of isochromans to isochromanones by activating O2

“…Based on the aforementioned tests and previous research, [49][50][51][52][53][54] we proposed two plausible reaction pathways for the oxidation of isochromans to isochromanones (Scheme 3b).…”

“…Based on the aforementioned tests and previous research, 49–54 we proposed two plausible reaction pathways for the oxidation of isochromans to isochromanones (Scheme 3b). PMoV-Co is activated by heating O 2 and H 2 O to produce intermediate [PMoV-Co] ′ and hydroxyl radicals.…”

New two fold interpenetrating 3D polyoxovanadate-based metal–organic framework as bifunctional catalyst for the removal of 2-chloroethyl ethyl sulfide and phenolic compounds

“…[33]. Reasonable assembly of metalorganic cationic structural units and POVs can not only enrich the structure of this type of solid-phase material but also facilitate the synergistic effect of metal ions, organic ligands, and POVs to optimize the properties [34][35][36][37][38]. Chen et al synthesized a discrete tetranuclear vanadium metal-organic complex…”

Two binuclear Ni-inserted polyoxotantalates based on {NiTa10O32} units with catalytic activity

“…Polyoxometalates (POMs) are a class of metal-oxo clusters with diverse structures and excellent properties and they have potential application in photochemistry, catalysis, proton conductivity and magnetism. 1–4 According to the literature on POM chemistry, in the last two centuries, V-, Mo- and W-based POMs have rapidly developed because they can be synthesized from simple materials (such as Na 3 VO 4 , Na 2 WO 4 or Na 2 MoO 4 ) through acidification, and their stable pH range is relatively wide. 5 On the contrary, POTa clusters are less studied, which may be attributed to several reasons: (a) soluble precursors of POTa are rare.…”