Chemical Basics and Applications

Although the homologation reaction was originally restricted to aliphatic alcohols, its scope has been extended to a broad range of basic organic chemicals (eq. (3)). 

Within this scope, homologation reactions are all variants of enlarging the carbon chain in a oxygen-containing molecule by one C atom with the use of syngas. 

Thus the homologation reaction can be used, for example, for the synthesis of acetaldehyde from methanol [48], propionic acid from acetic acid [47], or ethyl acetate from methyl acetate [50]. Styrene may be produced from toluene by oxidation to benzyl alcohol [51] and homologation to 2-phenylethanol, which in turn can be dehydrated to styrene. From the chemical point of view, the applications of homologation reactions are broad and useful. But, as mentioned before, low selec- 

[bar] Temp. [°C] Catalyst Promoters Remarks Conversion [%] Product/ selectivity [%] By-product selectivity [%] Ref. 

320 260 Co,(CO)s Nal, NajCOj CO and water conversion 42 Ethanol/29 Methyl acetate/14 1,1-dimethoxy-ethane/7 [17] 

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