In the presence of oxygen, diethylzinc can be used to promote radical additions to C=N bond containing radical accepters and to enones. In these reactions, it plays at the same time the role of the initiator and the role of the chain-transfer reagent. A parallel with triethylborane-mediated reactions is established. The methodology is restricted to secondary and tertiaryalkyl radicals generated from the corresponding alkyl iodides. It could not be extended either to C=C bond containing radical accepters such as methyl methacrylate and nitrocyclohexene or to diethylazodicarboxylate.