Cyclopentenes cobalt carbonyl catalyst

Addition of carbon monoxide and hydrogen to an alkene linkage in the presence of cobalt catalysts gives aldehydes in an average yield of 50%. The reactions may be carried out in the usual hydrogenation apparatus. The poisonous properties of carbon monoxide and cobalt carbonyls call for considerable care. Compounds made by hydroformylation include cyclopentanealdehyde from cyclopentene (65%), /3-carbethoxy-propionaldehyde from ethyl acrylate (74%), and ethyl /3-formylbutyrate from ethyl crotonate (71%). 

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