Methyl iodide, reaction with amyl sodium

That a metal-halogen interchange, (c), does take place under conditions of the Wurtz reaction has been shown by the isolation of amyl iodide in 47% yield from the reaction of amyl sodium with methyl iodide.10... 

Disodium phthalocyanine may be prepared by the reaction of phthalo-nitrile with sodium amyloxide in amyl alcohol (10), or from sodium hydride and phthalonitrile (52). It does not sublime, and is readily demetallated by methanol and less readily by the higher alcohols (75). The complex reacts with methyl iodide in ethyl alcohol to give only the unmetallated derivative (10). 

Two months later (June 1855) Wurtz announced the successful synthesis of five novel mixed or asymmetric hydrocarbons (ethyl-butyl, ethyl-amyl, butyl-amyl, butyl-caproyl, and methyl-caproyl), all produced by the reaction of iodides of the radicals with sodium metal— e.g., ethyl iodide and butyl iodide react with sodium to yield, inter alia, the new substance ethyl-butyl. This is precisely what Hofmann and Brodie had tried but failed to accomplish, pursuing Williamson s "mixed ether" strategy, in December 1850. It is a testament to Wurtz s experimental artistry that he succeeded. ... 

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