In-Situ generation of surface-active HCo(CO)y like intermediate from gold supported on ion-promoted Co3O4 for induced hydroformylation-hydrogenation of alkenes to alcohols

Stable and Surface‐active Co Nanoparticles Formed from Cation (x) Promoted Au/x‐Co3O4 (x=Cs) as Selective Catalyst for [2+2+1] Cyclization Reactions

“…To afford a bimetallic structure, it essential to support gold nanoparticles on selected metal oxides, even though the support‘s choice affects the catalyst‘s performance and durability. Gold nanoparticles supported on metal oxides have been reported for reactions such as alkoxy‐carbonylation of epoxide and hydroformylation [25,26] . In these reactions, the metal nanoparticles assisted in the spillover of H 2 and CO on the catalyst surface, thereby forming a cobalt carbonyl complex as the active catalytic site that catalyzed the reaction.…”

“…The nanomaterial‘s surface basicity was evaluated by CO 2 ‐TPD measurements because of the substantial role of basicity in the carbonylation reactions involving CO gas [25] (Figure 1a and Figure S4). The significant role of ion‐promoters in catalytic reactions is still unclear, despite it being mentioned in literature.…”

“…Gold nanoparticles supported on metal oxides have been reported for reactions such as alkoxy-carbonylation of epoxide and hydroformylation. [25,26] In these reactions, the metal nanoparticles assisted in the spillover of H 2 and CO on the catalyst surface, thereby forming a cobalt carbonyl complex as the active catalytic site that catalyzed the reaction. For the intra-and intermolecular reaction reported by Hamasaki and co-workers, [27] the dissolution of the active cobalt carbonyl species is necessary for the reaction to proceed smoothly and at a longer reaction time; the active cobalt species leached out of the catalyst into the reaction mixture, and hence, recyclability was not achieved.…”

“…Recently, we reported that alkali-promoted catalysts are effective for carbonylation reactions, such as hydroformylation. [25] The alkali ions were used to modify and stabilize the mesoporous cobalt oxide, which minimized leaching of the active metallic Co species and improve the catalyst's overall binding properties and performance. Also, an evident correlation was found between the ion-promoted catalyst's reduction temperature and surface basicity with its catalytic performance.…”

Reusable Catalysts for Hydroformylation‐Based Reactions

“…Another heterogeneous cobalt catalyst for the hydroformylation/hydrogenation of alkenes was developed by Meijboom et al [141] In this study 5 % wt Au/CsÀ Co 3 O 4 was prepared and evaluated in the direct synthesis of alcohols, starting from linear olefins. The reaction of oct-1-ene was carried out in THF at a temperature of 140°C, using 40 bar of CO/H 2, (1 : 2) and 40 mg of catalyst, for 16 h, leading to 92 % conversion and 95 % selectivity for nonan-1-ol (Table 1, entry 4).…”