Abstract: The preparation of 2,3-dialkoxypropanals of the general formula I ##STR1## in which R.sup.1 and R.sup.2 denote C.sub.1 -C.sub.8 -alkyl or C.sub.5 - or C.sub.6 -cycloalkyl which may or may not bear substituents which are inert under the conditions of the reaction, wherein a 1,2-dialkoxy ethene of the general formula IIR.sup.1 O--HC.dbd.CH--OR.sup.2 (II)is reacted with carbon monoxide and hydrogen in the presence of a rhodium-containing catalyst.

Abstract: Alkyl pentenoates are prepared by(a) reacting butadiene or a butadiene-containing hydrocarbon mixture with carbon monoxide and an alkanol in the presence of a tertiary aromatic heterocyclic nitrogen base and a cobalt carbonyl catalyst at from 80.degree. to 160.degree. C. under from 100 to 1,000 bar to obtain a reaction mixture which contains alkyl pentenoate, C.sub.6 -diester, tertiary nitrogen base, alkanol, butadiene, hydrocarbon and by-product,(b) substantially removing from the reaction mixture obtained any excess hydrocarbon, nitrogen base, alkanol and alkyl pentenoate by distillation to obtain a residue which contains cobalt carbonyl catalyst,(c) bringing the residue which contains cobalt carbonyl catalyst into contact with a mixture of carbon monoxide and hydrogen at elevated temperature and elevated pressure, and(d) recycling the residue which contains cobalt carbonyl catalyst into alkyl pentenoate synthesis stage (a).

Abstract: .omega.-Formylalkanecarboxylic esters are prepared by hydroformylation of an alkenecarboxylic ester with carbon monoxide and hydrogen at elevated tempertures and under superatmospheric pressure in the presence of a cobalt carbonyl complex by a process in which an .alpha.,.beta.-unsaturated alkenecarboxylic ester is hydroformylated in the presence of from 0.01 to 1 mol %, calculated as cobalt, of a cobalt carbonyl complex, while maintaining a conversion of from 10 to 70% of .alpha.,.beta.-unsaturated alkenecarboxylic esters.

Abstract: Alkyl pentenoates are prepared by reacting butadiene with carbon monoxide and an alkanol in the presence of a cobalt carbonyl complex and a tertiary, aromatic heterocyclic nitrogen base at from 80.degree. to 160.degree. C. under from 100 to 1,000 bar in the presence of from 0.1 to 10% by volume of hydrogen, based on the amount of carbon monoxide used.

Abstract: Aqueous solutions which are obtained in the carbalkoxylation of olefinically unsaturated compounds and contain heterocyclic aromatic nitrogen bases, their transformation products and lower fatty acids and/or their salts are treated by a process in which (a) the aqueous solution is heated to 150.degree.-300.degree. C. under from 10 to 300 bar and (b) heterocyclic aromatic nitrogen bases which are formed again from the transformation products are then separated off.

Abstract: Carbalkoxy-containing aliphatic compounds are prepared continuously by reacting an olefinically unsaturated aliphatic compound with carbon monoxide and an alkanol in the presence of a cobalt carbonyl catalyst and a tertiary nitrogen base at from 80.degree. to 200.degree. C. and under from 100 to 1,200 bar by an improved process in which carbon monoxide is circulated, and a carbon dioxide content of from 0.1 to 2% by volume is maintained in the carbon monoxide fed to the reaction.

Abstract: 1,1,2-trialkoxyethanes I ##STR1## where R.sup.1, R.sup.2 and R.sup.3 are each C.sub.1 -C.sub.8 -alkyl and R.sup.1 and R.sup.2 may furthermore be bonded to one another to form a 5-membered to 7-membered ring, are prepared by reacting a formaldehyde dialkyl acetal II with carbon monoxide and hydrogen, from 0.5 to 1.5 moles of hydrogen being used per mole of carbon monoxide, and with not less than 1 mole of alcohol R.sup.3 OH per mole of formaldehyde dialkyl acetal under superatmospheric pressure and at elevated temperatures in the presence of a catalyst which is formed from a cobalt carbonyl compound and a trivalent organic compound of the formula III ##STR2## where A is phosphorus, arsenic, antimony or bismuth and R.sup.4, R.sup.5 and R.sup.6 are each an organic radical.

Abstract: Ethylene glycol is prepared from carbon monoxide and hydrogen in homogeneous liquid phase under superatmospheric pressure and at elevated temperature in the presence of a rhodium-containing catalyst and in the presence of an organic solvent, the organic solvent used being a C.sub.2 -C.sub.20 -n-alkanol and the concentration of this alkanol, based on the total amount of the mixture, constantly being maintained at not less than 50% by weight.

Abstract: Ethylene glycol is prepared from carbon monoxide and hydrogen in a homogeneous liquid phase under superatmospheric pressure and at elevated temperatures in the presence of a rhodium-containing catalyst and in the presence of a porphyrin as organic nitrogen-containing promoter.