A Cooperative Effect in a Novel Bimetallic Mo–V Nanocomplex Catalyzed Selective Aerobic C–H Oxidation

Abstract

In this study, a new heterobimetallic Mo(VI)–V(V) organosilicon Schiff base complex has been prepared and characterized by different techniques, such as FTIR, Raman, MS, ICP-AES, TGA, and XPS. The bimetallic nanocomplex, revealed by TEM images, showed high oxidation stability and desired activity in the aerobic oxidation of a structurally diverse set of benzylic alcohols in ethanol as a safe solvent. Further, oxidation of benzylic hydrocarbons successfully occurred, producing the target compounds in high yields and excellent selectivities. Our results demonstrated a cooperative effect between Mo(VI) and V(V) as redox active sites in an organosilicon Schiff base framework. A facile and practical reusability of the solid catalyst at the end of the reaction was observed.

Hierarchically Porous Hydrothermal Carbon Microspheres Supported N-Hydroxyphthalimide as a Green and Recyclable Catalyst for Selective Aerobic Oxidation of Alcohols

“…Selective oxidation of alcohols with molecular oxygen to valuable functional chemicals plays significant roles in organic synthesis and industrial application. − As powerful organocatalysts, N -hydroxyphthalimide (NHPI) and its derivatives have attracted increasing interest for the last few decades, in virtue of their remarkably high efficiencies in aerobic oxidation reactions. − Since Ishii and co-workers introduce NHPI/metallic salt systems to promote the oxidation of alkanes and alcohols with molecular oxygen, considerable progress has been made to develop many catalytic systems including the discovery of various metal-based and metal-free initiators and the synthesis of NHPI derivatives toward the oxidation of various substrates. − However, typical NHPI-based catalysts are generally homogeneous and are not easily recoverable after oxidation. Additionally, the work-up procedure is inconvenient and inevitably generates a lot of waste.…”

Ligand coordination sphere effect of Schiff base cis‐dioxomolybdenum(VI) complexes in selective catalytic oxidation of alcohols

“…Recently, several Schiff base molybdenum(VI) complexes have been developed and used as catalysts for various oxygen atom transfer reactions, such as olefins epoxidation, 29–31 sulfides oxidation, 32 and alcohols oxidation 33 . Regarding alcohol oxidations, various Schiff base molybdenum complexes, such as magnetic complex, 34 Mo−V bimetallic complex, 35 and μ ‐O{MoO 2 } 2 core complex, 36 have been evaluated in alcohol oxidation with TBHP or H 2 O 2 as oxidants yielding the corresponding aldehydes or ketones. Nevertheless, dioxomolybdenum(VI) complexes 37,38 and peroxo‐molybdenum(VI) complexes 39,40 have been used for olefin epoxidation but not been fully exploited as catalysts in alcohols oxidation.…”

Aerobic Oxidation of Fluorene to Fluorenone over Copper-Doped Co3O4 with a High Specific Surface Area

“…Nevertheless, to improve the performance, a catalyst is needed for the process; for example, heterogeneous catalysts such as noble metals, metal–organic framework, and metallic organ silicon Schiff base complex have been used. − Moreover, N -hydroxyphthalimide, as a radical initiator, is needed. Hence, a heterogeneous catalyst for the process without addition of an initiator is highly demanded.…”