759.    DUPONT, G., PIGANIOL, P., AND VIALLE, J.  [The Oxo Reaction and Its Mechanism.]  Bull. Soc. Chim., France, 1948, pp. 529-532; Chem. Abs., vol. 42, 1948, p. 7232.

     Instead of the formation of the intermediate RCH-CHR-CO (I) when CO reacts


with olefins in the presence of metallic carbonyls, the authors propose the existence of a combination of Ni or Co carbonyl with a reactive compound, A.H (H2, H2O, ROH, R2NH, etc.).  This complex (II) reacts with the olefin in the presence of CO to regenerate the metal carbonyl and give III:


                        /      \





                       /        \

(OC)3         Ni           A+CO+RCH : CHR→Ni(CO)4 +




RCHCH2R (III).  It is stated that number I has been


AC : O

isolated from these reactions and that they do not occur unless A.H is present.  C2H2, CO and Ni (CO)4 in the presence of a little HCl and alcohol at 50 give a 50% yield of polymers of CH2 : CHCO2Et and CH2 : CHCO2H.  1-Hexene, alcohol, CO, and Co(CO)4 at 180 and 300 kg. pressure for 7 hours give 70% of a mixture of Me(CH2)5CO2Et and Me(CH2)3 CHMeCO2Et.  Cyclohexene under similar conditions gives 37% C6H11CO2Et.  Replacing the alcohol with H2O gives the acid.  Me hendecenoate gives a mixture of diesters.  Compounds with double bonds next to a tertiary C (carvomenthene and pinene) give little, if any, reaction.