Carboxylic acid promoted ruthenium catalysis

In this paper we disclose the syngas homologation of carboxylic acids via ruthenium homogeneous catalysis. This novel homologation reaction involves treatment of lower MW carboxylic acids with synthesis gas (C0/H2) in the presence of soluble ruthenium species, e.g., Ru02, Ru3(C0)12, H4Ru4(C0)12, coupled with iodide-containing promoters such as HI or an alkyl iodide (1). 

Carborundum, silver on, 27 10-12 3-Carboxy - 2,2,5,5,- tetramethylpyrrolidin-1-oxy m-nitrophenyl ester, enantiomeric specificity in reactions of cyclohexaamy-lose and cycloheptaamylose on, 23 233 Carboxylate ions, 32 117-118 Carboxybc acids a, 3-unsaturated, 25 109 hydrogenation of, 25 107-115 ketonization of, 24 35-37 Lewis base-promoted ruthenium catalysis, 32 389, 400... 

Synthesis of Carboxylic Acid Esters. The preparation of aliphatic carboxylic acid esters from synthesis gas and the corresponding acid is illustrated by the experimental data summarized in Table VI. Here propionic acid is the coreactant (eq. 21) and CO hydrogenation yields substantial quantities of Cx C4 alkyl propionates. Some 14 catalyst combinations of ruthenium with quaternary Group 5B and alkali metal promoters have been considered. The important features of the catalysis are as follows ... 

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