It works, but it seems overly complicated (it uses processes which we have not studied at school). After some thought, I've vome up with this:
Dehydrate the ethanol withc conc. warm H2SO4 to give ethene. This is then oxidised with KMNO4 in alkaline conditions to give ethan-1,2-diol. This is then reacted in a substitution reaction with KCN to give butan-1,4-dinitrile. You then reduce that with LiAlH4 in ether to give butan-1,4-diamine.
Simpler, no?