Green and Direct Synthesis of Benzaldehyde and Benzyl Benzoate in One Pot

Abstract

High yields of valued benzaldehyde and benzyl benzoate are obtained in one pot starting from benzyl alcohol using oxygen as only oxidant under mild conditions (2 bar O2, 100 °C) along with an ultralow amount (0.02 mol %) of Au nanoparticles heterogenized over a spherical ORMOSIL mesoporous support. The process is remarkably selective and the catalyst is stable.

Silica Nanoparticles Decorated with Polymeric Sulfonic Acids Trigger Selective Oxidation of Benzylic Methylenes to Aldehydic and Ketonic Carbonyls

“…This result further suggests that sulfonic acid groups of the heterogeneous material do not easily leach and are the active sites of the catalyst. Although the reactivated catalyst showed a more rapid deactivation than the fresh one (entries 12–16), the present material is chemically stable and can easily trigger the selective oxidation of hydrocarbons for more than 300 turnovers (Table ), outmatching most of their metal-based peers. − …”

“…There are several elegant reports on the oxidation of toluene to benzaldehyde. This is achieved using a metal-based catalyst and H 2 O 2 or molecular O 2 , which are clean oxidants, although with either low yields or poor selectivity. − On the other hand, such limitations can be efficiently countered by using proper catalysts in combination with molar excesses of hypervalent iodine reagents or organic peroxides, − which ultimately affect however the environmental cost of the whole process. Most of these methods require the use of transition-metal catalysts too. , We are unaware of reports on the direct oxidation of inactivated , benzylic methylenes to the corresponding carbonyls mediated by an organic acid catalyst.…”

Metal–Support Interaction in Gold Zeolitic Octahedral Metal Oxide and the Catalytic Activity for Low-Temperature Alcohol Oxidation

“…The selectivities to benzaldehyde and benzyl benzoate were 21 and 76%, respectively (Table , entry 1). Benzyl benzoate was derived from the oxidative esterification of benzyl alcohol, , which was the major product of benzyl alcohol oxidation catalyzed by Au 1% /o-MoVO-N400. Oxidation of benzyl alcohol catalyzed by Au 1% /o-MoVO-N400 was carried out to understand the influence of the reaction conditions on the selectivities to benzaldehyde and benzyl benzoate.…”

Sulfonic Acid-Functionalized Inorganic Materials as Efficient Catalysts in Various Applications: A Minireview

“…In addition to the changes in proportion between these peaks, when functionalized, a new set of peaks in the range {−45;−80} ppm appears giving evidence for the covalent incorporation of the functional groups. The peaks correspond to three different environments for the siloxanes groups: T 1 , T 2 , and T 3 assigned respectively to [T m = RSi(OSi) m (OMe) 3-m ] [11,13,[81][82][83][84][85]. Khrisna et al [86], for example, attribute the presence of more T 3 species in RSO 3 H-MCM-41 compared to RSO 3 H-SBA-15 to a higher number of Q 3 in the bare MCM-41 precursor indicating a more efficient condensation.…”