Synthesis of Oxygenates from Syngas by Homogeneous Catalysts

Synthesis of Oxygenates from Syngas by Homogeneous Catalysts 

Oxygen-containing Cl and C2 molecules can be efficiently synthesized from CO and H2 (syngas) using cobalt, rhodium, and ruthenium catalysts. Among these catalysts, ruthenium is very efficient and selectively provides products with less than C2 units [8,9] this is in contrast to the Rh and Co catalysts, which produce byproducts with more than C3 units (Eq. 11.2). 

A Ru3(CO)i2/I /acid/phosphine oxide catalyst [8, 9] or a Ru3(CO)i2/Cl catalyst [10] gives ethanol together with methanol (Eq. 11.3). 

When ethanol is produced, methanol is formed in the first step, and is then homologated. Dombek reported that ruthenium complexes are effective for the production of ethylene glycol at 340 atm and below, especially in the presence of iodide (Eq. 11.4) [11]. 

Knifton reported that the combination of ruthenium complex/phosphonium salt, such as Ru02/Bu4PBr and Ru(acac)3/Bu4PBr, is a good catalyst for the synthesis of ethylene glycol together with methanol and ethanol [12]. 

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