4.     ---------------. [ADKINS, H., AND KRSEK, G.]  Hydroformylation of Unsaturated Compounds With a Cobalt Carbonyl Catalyst.  Jour.  Am. Chem. Soc., vol. 71, 1949, pp. 3051-3055.

  Hydroformylation of several unsaturated hydrocarbons, ethers, and esters, through the use of dicobalt octacarbonyl in benzene at 100-300 atm. of CO and H₂, has given good yields of aldehydes free of isomers (see Adkins and Kkrsek, abs. 3).  The reaction of substituted ethylenes of the types RCH=CH₂ and R₂C=CH₂ have given in 6 cases aldehydes of the type RCH₂CH₂CHO and R₂CHCH₂CHO; however, where R was phenyl, 1-naphthyl, n-butoxy, acetoxy, and ethoxymethyl, aldehydes of the type RCH (CH₃)CHO.  Three alkenes of the type RCH=CHR have given good yields of a single aldehyde.   Some limitations of the reaction, due to formation of mixtures of aldehydes or failure of the hydroformylation reaction to take place, are illustrated.  The presence of a S-containing compound in the reaction mixture did not significantly poison the catalytic activity of the benzene-soluble cobalt carbonyl catalyst.  This catalyst has proved to be effective for the hydrogenation of the carbon to carbon double bond in certain a-. B-unsaturated carbonyl compounds.