Abstract: .omega.-Formyl-C.sub.4 -C.sub.20 -alkanecarboxylic esters are prepared by reacting C.sub.4 -C.sub.20 -alkenecarboxylic esters with carbon monoxide and hydrogen at from 30.degree. to 150.degree. C. and under from 0.01 to 30 bar in the presence of rhodium carbonyl complexes which are modified with polyphosphites.

Abstract: Rhodium hydroformylation catalysts containing bisphosphite ligands of the formula I ##STR1## where -X- is a divalent bisarylene radical or R.sup.1,w is a divalent arylene, bisarylene or alkylene radical, andR.sup.1 and R.sup.2 are identical or different and are substituted or unsubstituted alkylene or ortho-arylene.

Abstract: Rhodium hydroformylation catalysts containing bisphosphite ligands of the formula I ##STR1## where --X-- is a divalent bisarylene radical or R.sup.1,W is a divalent arylene, bisarylene or alkylene radical, andR.sup.1 and R.sup.2 are identical or different and are substituted or unsubstituted alkylene or ortho-arylene.

Abstract: Olefinically unsaturated compounds are hydroformylated in an organic reaction medium with the aid of rhodium complex catalysts which are soluble in the reaction medium by performing the reaction in the presence of water-insoluble rhodium complex catalysts and also in the presence of arylthiols of the general formula IAr--SH Iwhere Ar is substituted or unsubstituted aryl.

Abstract: Alkanals having a 2-alkyl branch are obtained from mixtures which contain the alkanals having a 2-alkyl branch in addition to n-alkanals, 3-alkylalkanals and/or further isomers by a process in whicha) the alkanal mixture is reacted with an aqueous formaldehyde solution in the presence of a secondary amine and of a carboxylic acid as a catalyst,b) the aqueous phase containing the catalyst and any unconverted excess formaldehyde is separated off andc) the alkanals having a 2-alkyl branch are isolated by distillation from the condensates of the other alkanals with formaldehyde.

Abstract: Octadienols are prepared by teleomerization of 1,3-butadiene with water in the presence of carbon dioxide and a catalyst system comprising a palladium compound and a tertiary phosphorus compound by performing the reaction in the presence of a strong non-coordinating acid.

Abstract: A process for the preparation of carbonyl compounds by catalyzed isomerization of allyl alcohols in a tertiary phosphine or phosphite ester in the presence of a rhodium compound at a temperature of from 80.degree. C. to 180.degree. C., a carrier gas being passed through the reaction mixture and the carbonyl compound being separated from the emergent gas mixture by cooling.

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: 2(5H)-furanones I ##STR1## where R.sup.1 and R.sup.2 are each hydrogen, C.sub.1 -C.sub.6 -alkyl, C.sub.5 - or C.sub.6 -cycloalkyl, C.sub.7 -C.sub.12 -aralkyl or aryl, are prepared by heating a 3-formylcarboxylate or 3-formylcarboxylic acid II ##STR2## where R.sup.3 is hydrogen, C.sub.1 -C.sub.12 -alkyl, C.sub.5 - or C.sub.6 -cycloalkyl, C.sub.7 -C.sub.12 -aralkyl or aryl, to 100.degree.-450.degree. C. in the presence of an acidic catalyst.