Oxidation of ethanol by cobalt, iron, and rhodium complexes

Abstract

Aerial oxidation of ethanol in the presence of an aromatic azo-compound and COX, (X = F, CI, O,CMe, or C104) or iron(ll1) chloride gives a stoicheiometric amount: of acetaldehyde with CoCI,, Co[O,CMe],, and FeCI,, but no oxidation occurs with CoF, and CO[CIO,]~. Addition of nitrogen-donor ligands promotes the oxidising activity in CoF,, and this effect is discussed and a mechanism is proposed for the oxidation. The cobalt(ii)chloride-aromatic azo-compound combination effects slow catalytic oxidation of a potassium propionate-propanol mixture. Several rhodium complexes which catalytically oxidise ethanol are reported, and 5% Rh-C dehydrogenates ethanol smoothly a t its boiling point.* Throughout this paper: 1 mmHg x 13.6 x 9.8 Pa.

Molecular orbital analysis of the bonding capabilities of carbon disulfide and carbon dioxide toward transition metal fragments

“…We have then considered the slipping of CS2 off the L3M main axis. The and angles defined in 7 have been varied independently, but Figure 2 shows the evolution of the four upper orbitals of Figure 1 as a function of alone, the value being fixed at 150°. The five orbitals underneath those four reported in Figure 2 spread out a little but remain substantially compact.…”

Supported Palladium Nanoparticle Catalyzed α-Alkylation of Ketones Using Alcohols as Alkylating Agents

“…α- Alkylation of ketones is the most versatile carbon–carbon bond formation reaction in organic synthesis. These reactions are conventionally performed using toxic alkyl halides as alkylating agents in the presence of strong bases. , In recent years alcohols have been directly used as greener alkylating agents over alkyl halides in transition metal catalyzed α-alkylation of ketones using a hydrogen borrowing strategy as a promising alternative approach. − Inspired by the work of Grigg et al, who used alcohols as alkylating agents, , many groups have envisioned a variety of alkylation methods using iridium, − ruthenium, − rhodium, , and other transition metal catalysts. − Methanol is an important feed stock chemical, and its dehydrogenation reactions are a valuable but challenging goal. Beller and Grutzmacher independently reported Ru-catalyzed dehydrogenation of methanol to hydrogen and carbon dioxide. , Krische et al reported Ir-catalyzed coupling of methanol with allenes and Glorius et al reported activation of methanol for C–N bond formation reaction .…”

“…1,2 In recent years alcohols have been directly used as greener alkylating agents over alkyl halides in transition metal catalyzed αalkylation of ketones using a hydrogen borrowing strategy as a promising alternative approach. 3−6 Inspired by the work of Grigg et al, who used alcohols as alkylating agents, 7,8 many groups have envisioned a variety of alkylation methods using iridium, 9−15 ruthenium, 16−20 rhodium, 21,22 and other transition metal catalysts. 23−31 Methanol is an important feed stock chemical, and its dehydrogenation reactions are a valuable but challenging goal.…”

Rhodium‐Catalyzed Ketone Methylation Using Methanol Under Mild Conditions: Formation of α‐Branched Products

“…Since a discovery by Grigg et al, who used alcohols as alkylating reagents,[ 2 ] the transition-metal-catalyzed α-alkylation of carbonyl compounds using hydrogen borrowing has emerged as a productive area of research. Contributions from the groups of Cho/Shim,[ 3 ] Ishii,[ 4 ] Nishibayashi,[ 5 ] Ramón/Yus,[ 6 ] Park,[ 7 ] Uozumi,[ 8 ] Williams,[ 9 ] and others[ 10 ] have demonstrated variations of such alkylation reactions using different metal catalyst systems (Scheme 1 A ).…”