2531. NIENBURG, H. (Badische Anilin- u. Soda-Fabrik). [Organic Compounds Containing Oxygen.] German Patent 800,400, Nov. 2, 1950; appl. filed Oct. 2, 1948 (Cl. 12 o-7.03). Chem. Abs., vol. 45, 1951, p. 1625.

Process of preparing organic compounds containing O by reaction of CO and H2 with diolefins in the presence of hydrogenation catalysts is improved by using dimerized diolefins as reactants. The dimerization is effected by heating the diolefins several hours at 200-250. Treating dimerized butadiene thus in presence of a Co-kieselguhr catalyst with a CO-H2 mixture (1:1) at 120 and 200 atm. for 60-80 min., replacing the CO-H2 mixture by H2 (100 atm.), heating the mixture 1 hr. at 120 to decompose the Co carbonyl compounds, and distilling the reaction product in vacuo yields a cyclic singly unsaturated C9-aldehyde, b.18 93-98. The analogous treatment of dimerized isoprene yields a cyclic C11-aldehyde, colorless oil, b.14 130-135, and small quantities of the corresponding C11-alcohol.

NIENBURG, H. See abs. 1846.