Also known as: Wurtz coupling
The Wurtz reaction is an organic reaction used to couple two alkyl halides to form an alkane using sodium metal. The mechanism begins with a single electron transfer (SET) from sodium metal to the alkyl halide, which dissociates to form an alkyl radical and sodium halide salt. Another molecule of sodium performs another SET to the alkyl radical to form a nucleophilic carbanion. The carbanion then attacks another molecule of alkyl halide in a nucleophilic substitution reaction (SN2) to form the final coupled product and another molecule of sodium halide salt. 
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