Reduction of 1,4-benzoquinone in the synthesis of 1,5-diazocane Synthesize 1,5-diazocane using only benzene as a source of
  carbon atoms, and ammonia as the only source of nitrogen atoms.


My attempt: Noticing that the target compound has split the benzene ring, I attempted to split the benzene ring as well. I thought of two options:


H2/Pt at high temperature and pressue
Creation of phenol and subsequent oxidation


As the first process would create cyclohexane and be difficult to manipulate, I went with the second option. To synthesize phenol from benzene, I used a nitration, followed by reduction to create aniline, then used nitrous acid to create the benzenediazonium salt, and decomposed the salt in the presence of  water to create phenol. After the oxidation of phenol I got 1,4-benzoquinone. 

Now, realizing that I would need to create 1,3-propandial in order to use $\ce{NH3/NaBH3CN}$ to create 1,5-diazocane, I attempted to make 1,3-propandial from 1,4-benzoquinone. Ozonolysis of 1,4-benzoquinone produces 2-oxo,1,3-propandial, which has an extra carbonyl group. Because of the many carbonyl groups involved in this compound, I was thinking of removing the carbonyl groups directly from benzoquinone, and doing an ozonelysis from there. However, I was not sure if any standard carbonyl reactions, such as the Wolff-Krishner or the Clemmensen reaction could be applied to remove the carbonyls, seeing as they are heavily resonance stabilized. 

Therefore, I was wondering if these reactions do proceed on benzoquinone, and if not, then what other plausible ways of synthesizing 1,5-diazocane exist?
Here is a relatively straightforward synthesis of 1,5 diazocane that uses the Beckmann rearrangement as a key step. The Beckmann rearrangement is a useful synthetic tool for converting ketones to amides.  If the carbonyl is in a ring, then conversion to the amide will enlarge the ring by one nitrogen atom.



The novel twist in the following synthesis is to perform a double Beckmann rearrangement in the penultimate step.




heating benzene with concentrated sulfuric acid containing excess sulfur trioxide (oleum) will lead to the disulfonated product, benzene-1,3-disulfonic acid
heating the disulfonic acid with potassium carbonate produces resorcinol (see here)
treating resorcinol with hydrogen gas at low pressure over a rhodium catalyst yields 1,3-cyclohexanedione (see here)
hydroxylamine can be prepared by oxidizing ammonia with hydrogen peroxide to produce ammonium nitrite which can then be converted by a number of methods to hydroxylamine
the hydroxylamine is used in standard fashion to afford the bis-oxime (various oxime stereoisomers are likely produced, but this does not matter, all oxime stereoisomers will undergo the Beckmann rearrangement in the next step)
the bis-oxime is converted to the bis-amide through a double Beckmann rearrangement (see here for this specific conversion; note that the double Beckmann could afford isomers but only the desired isomer is produced; see the preceding link for the authors explanation as to why this is so)
finally, standard reduction of the bis-amide with $\ce{LiAlH4}$ and aqueous workup gives rise to the target molecule


The double Beckmann could also be run starting with 1,4-cyclohexanedione (readily prepared from benzene, see here).  1,4-cyclohexanedione has the advantage of symmetry - the first Beckmann rearrangement can produce only one isomer.  Although the second Beckmann rearrangement could produce 2 isomers, only the desired 1,5-diazocane-2,4-dione was isolated (see here).