Abstract The carbon monoxide uptake in the reaction of allylbenzene with CoH (CO) 4 in n- octane leading to acylcobalt tetracarbonyls and aldehydes is catalyzed by Co 2 (CO) 8. The rate is half order in Co 2 (CO) 8, first order in allylbenzene and shows a complex dependence in CoH (CO) 4 and CO. From kinetic experiments between 15 and 45 C the temperature dependence of the observed rate constant was determined. The complete ...