| Abstract
| - Evidence for single-electron transfer (SET) in the reactions oflithium aluminum hydride (LAH)with unhindered, saturated primary alkyl halides has not beenavailable. In this study, experimentshave been carried out that provide convincing evidence that theunhindered, saturated primaryalkyl iodide 1-iodooctane reacts with lithium aluminum deuteride (LAD)in a 1:0.2 ratio to form1-deuteriooctane with up to 38% incorporation of protium. Sincethe protium incorporation increasedas the reaction proceeded, studies involving the reaction of1-iodooctane with AlD3 (one of thebyproducts in the reaction of LAD with alkyl halides) were carried outin order to determine theeffect of AlD3. With AlD3, protiumincorporations as high as 84% were observed, indicatingthatthe reaction of AlD3 with 1-iodooctane proceeds via apathway that involves at least 84% radicalformation. The study also included the effect of reaction vesselsurface, concentration, and leavinggroup on the course of the reaction. Factors previously suggestedby Newcomb to explain the resultsof the reactions of LiAlH4 with cyclizable radical probes,e.g., a halogen atom radical-chain process,can be excluded as a valid argument in the present study.
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