nos 4 064 145 4 400 548 and 4 400 549 the pertinent portions of which are incorporated by reference herein it is especially preferred that the catalyst be a rhodium carbonyl triphenylphosphine complex catalyst such as hydridocarbonyltris triphenylphosphine rhodium i this complex may be written as hrh co pph 3 3 where ph represents a phenyl group preferably an excess of the phosphine ligand is added to provide additional triphenylphosphine an inert organic solvent is employed preferred organic solvents such as ethers ketones and tertiary amines including diethyl ether p dioxane tetraglyme methyl iso butyl ketone 2 undecanone triethylamine and tri n propylamine inert non polar compounds are also useful as solvents such as for example alkanes such as hexanes hexadecane aromatics such as benzene toluene ortho xylene meta xylene para xylene mixed xylenes ethylbenzene etc and mixtures thereof the temperature range which can be employed is a variable which is dependent upon experimental factors including the particular feedstocks employed the total pressure the mole ratio of hydrogen and carbon monoxide used the concentrations of reactants and catalyst among other things using 1 3 butadiene as a feedstock and rhodium carbonyl triphenylphosphine complex as a representative catalyst an operable range is from about 20 u00b0 c to 150 u00b0 c or more when superatmospheric pressures of greater than 100 psig are employed a narrower range of 50 u00b0 c to 120 u00b0 c represents the preferred temperature range the pressure range which can be employed is a variable which is also dependent on the factors mentioned.