The reaction of three different Grignard reagents with 2-bromooctane in the presence of small amounts of cobaltous bromide has been studied.Under the reaction conditions, the 2-octyl radical derived from the organic bromide largely(44-58%) disproportionated, forming a mixture of octane and octenes, and to a considerable extent(26-35%) dimerized.The gaseous products of the reaction have been analysed.The results were in accord with the free radical chain mechanism of these reactions.