Oxygen-containing organic compounds are obtained by treating a saturated monohydric aliphatic alcohol having up to 4 carbon atoms, an ether containing the radical of such an alcohol, or an ester of such an alcohol with a saturated fatty acid having up to 4 carbon atoms with carbon monoxide, with or without hydrogen, under a pressure exceeding 50 atmospheres and at a temperature between 180 DEG and 350 DEG C. in the presence of a catalyst containing a metal of the iron group, a halogen or halogen compound, and a complex-forming non-olefinic organic compound containing at least two functional groups of the same or different kind, selected from hydroxy, carboxylic acid, carboxylic acid amide, carboxylic acid nitrile, keto, amino or substituted amino group, capable of entering into complex combination with the metal of the iron group. The catalyst preferably contains the metal of the iron group in the form of a salt, e.g. of acetic, propionic or butyric acid. The halogen used is preferably iodine and specified halogen compounds are the free hydrogen halides or their salts or esters, e.g. hydrogen iodide, alkali metal iodides and alkyl iodides containing up to 4 carbon atoms, e.g. methyl or ethyl iodide. The carbonyl-forming iron group metal and the halogen may also be used in combination, e.g. in the form of cobalt iodide. Specified types of polyfunctional compounds are those containing the following combination of groups:-(a) H2N . . .OH, e.g. the amino phenols such as o-, m-, and p-amino phenol and C1-C4 alkyl substituted amino phenols, e.g. o-amino-p-cresol; amino alcohols such as mono-, di- and tri-ethanolamine, alkylol amines derived from mono and dialkyl amines containing alkyl radicals with up to 8 carbon atoms, e.g. monoethanol diethylamine, monoethanol octyl amine and diethanol butyl amine; (b) H2N . . . COOH, e.g. glycocoll, alanine, amino butyric acid, and anthranilic acid and its homologues containing hydrocarbon radicals with up to 4 carbon atoms; (c) HO . . . COOH, e.g. lactic acid, tartaric acid, citric acid, salicylic acid, and methyl salicylic acid; (d) O=C . . . COOH, e.g. alpha-ketopropionic acid and propionyl propionic acid; (e) O=C . . . C=O, e.g. acetyl acetone; (4) HO . . . OH, e.g. o-, m-and p-dihydroxybenzene and homologues thereof containing aliphatic hydrocarbon radicals with up to 4 carbon atoms; (g) NC . . . CN, e.g. aliphatic dinitriles containing 1 to 4 carbon atoms between the nitrile groups, e.g. malonic acid dinitrile and adipic acid dinitrile and (h) H2N . . . NH2, e.g. ethylene diamine and homologues thereof up to hexamethylene diamine. Polyfunctional compounds which contain more than two functional groups, e.g. amino hydroxy carboxylic acids or hydroxyketo carboxylic acids may also be used as may lactams derived from amino carboxylic acids e.g. butyrolactam or caprolactam. In addition to the polyfunctional compound other compounds which are known to act as activators for carbonylation catalysts of the Iron Group, e.g. carbonyls of the metals of the Iron Group or tertiary amines such as pyridine may be used and inert solvents which may be the reaction products themselves or aromatic, alicyclic, or aliphatic hydrocarbons or their halogen derivatives may also be used. A small amount of water may also be present. When hydrogen is used in admixture with the carbon monoxide the volume ratio of CO to H2 should preferably be at least 70 to 30. The process may be carried out batchwise or continuously and in the latter case the carbon monoxide may be fed co-currently or countercurrently to the starting material in a vertical reactor. The catalyst mixture employed may be recovered from the reaction mixture and returned to the reaction chamber. In examples: (1) a mixture of methanol, cobalt acetate, iodine, and glycocoll is treated with carbon monoxide at elevated temperature and pressure to yield a mixture of acetic acid and methyl acetate; instead of glycocoll there may be used di- or tri-ethanolamine, monoethanolethylamine, o-aminophenol, o-aminocresol, p-aminophenol, N-b -hydroxyethyliminodipropionic acid, p-aminosalicylic acid, pyrrolidone, anthranilic acid, a -ketopropionic acid, a mixture of a -ketopropionic acid and pyrrolidone, propionyl propionic acid, citric acid, acetyl acetone, hydroquinone, or ethylene diamine; (2) as in (1) except that m-aminophenol is used; (3) as in (2) except that methyl acetate is used instead of methanol and water is also present, no methyl acetate being formed in this case; 3(b) as in (3) except that methanol is used instead of methyl acetate, less water is used, and ethanolamine or triethanolamine is used instead of m-aminophenol, a small amount of methyl acetate being obtained in this case in addition to the acetic acid; (4) as in (1) except that salicylic acid, propionyl propionic acid, or hydroquinone respectively are used instead of glycocoll; (5) as in (2) except that b -ketopropionic acid is used instead of m-aminophenol and a small amount of pyridine is also present, cobalt propionate may be used instead of the acetate; (6) as in (2), except that adipic acid dinitrile is used, (7) as in (2) except that methyl acetate is used instead of methanol, succinic acid dinitrile is used instead of m-aminophenol, and cobalt propionate may be used instead of the acetate; (8) a mixture of ethanol, water, cobalt acetate (or propionate), iodine, and ethanolamine is treated with carbon monoxide at 300 DEG C. under 300 atmospheres pressure to yield propionic acid and a small amount of ethyl propionate; (9) a mixture of n-propanol, water, cobalt acetate, hydrogen iodide (57 per cent strength) and ethanolamine is treated with carbon monoxide as in (8) to yield a mixture of iso- and n-butyric acids; (10) as in (2) except that a mixture of n-propanol, iron carbonyl, iron acetate, iodine and m-aminophenol is used to yield a mixture of iso-and n-butyric acids; (11) a mixture of n-propanol, nickel acetate, iodine, a -ketopropionic acid and pyridine is treated with carbon monoxide as in (2) to yield a mixture of iso and n-butyric acid propyl ester; (12) as in (2) except that a mixture of methanol, nickel acetate, iodine, tartaric acid and pyridine is used; (13) as in (2) except that a mixture of methanol, iodine, m-aminophenol and iron carbonyl is used. Specification 699,556 is referred to.