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It was mentioned previously that cubane was first prepared in 1964 by Dr. Philip E. Eaton. He was partnered by Thomas W. Cole and together they successfully completed the first synthesis, shown schematically below:

Hint: Run the cursor over the image for further details of the synthesis.

Reactive enough to undergo dimerisation via a [4+2] cycloaddition reaction to give the ENDO cycloadduct The more reactive, bridgehead ketone group is protected by Ketal formation. The first occurance of a Hunsdiecker decarboxylation, firstly substitutes the caroxylic acid group and then removes it. The first occurance of a Hunsdiecker decarboxylation, firstly substitutes the caroxylic acid group and then removes it. The first occurance of a Hunsdiecker decarboxylation, firstly substitutes the caroxylic acid group and then removes it. The first occurance of a Hunsdiecker decarboxylation, firstly substitutes the caroxylic acid group and then removes it. Acid hydrolysis releases the protected ketone The second instance of a Hunsdiecker decarboxylation. The second instance of a Hunsdiecker decarboxylation. The second instance of a Hunsdiecker decarboxylation. The second instance of a Hunsdiecker decarboxylation.
N-bromosuccinimide acts as the reagent for a radical mediated allylic bromination reaction which is carried out in tetrachloromethane with heat as the initiator Bromine is added... ...and 2 moles of HBr are eliminated...
...to give a highly reactive enone.
Reactive enough to undergo dimerisation via a [4+2] cycloaddition reaction to give the ENDO cycloadduct
The more reactive, bridgehead ketone group is protected by Ketal formation.
Photochemical energy is required to promote the [2+2] intramolecular cycloaddition reaction.
The acid mediated oxidation of the ktone group to a carboxylic acid.
The first occurance of a Hunsdiecker decarboxylation, firstly substitutes the caroxylic acid group and then removes it. The first occurance of a Hunsdiecker decarboxylation, firstly substitutes the caroxylic acid group and then removes it.
The first occurance of a Hunsdiecker decarboxylation, firstly substitutes the caroxylic acid group and then removes it.
Acid hydrolysis releases the protected ketone
The second instance of a Hunsdiecker decarboxylation.
The second instance of a Hunsdiecker decarboxylation.
The second instance of a Hunsdiecker decarboxylation.

image of molecule taken from
http://cst-www.nrl.navy.mil/lattice/struk/c8h8.html

This, however, was soon simplified by N.B.Chapman who condensed the process to give cubane-1,4-dicarboxylic acid in five steps and so cubane in six:

In 1966 J C Barborak et al discovered yet another new synthesis of cubane. It was slightly unconventional in the fact that it utilised cyclobutadiene as a key substance to the process. Before this,cyclobutadiene was usually unavailable for the purposes of organic chemistry due to it's instability. The shorter synthesis is shown below:
Decomposition in presences of 2,5-dibromobenzoquinone gives... Irradiation, in benzene, with a mercury lamp initiates the intramolecular [2+2] cycloaddition reaction. Treatment with KOH at 100 ºC gives the cubane-1,3-dicarboxylic acid Decarboxylation via thermal degradation of di-t-butyl perester
Decomposition in presences of 2,5-dibromobenzoquinone gives...
...the endo adduct.
Irradiation, in benzene, with a mercury lamp initiates the intramolecular [2+2] cycloaddition reaction.
Treatment with KOH at 100 ºC gives the cubane-1,3-dicarboxylic acid
Decarboxylation via thermal degradation of di-t-butyl perester

 

Since the synthesis of the cubane-1,4-dicarboxylic acid has become shorter and easier, a new decarboxylation method has also devised to give increased yields of the final cubane product. This has allowed the scale of production reach multikilogram batches in places (Fluorochem in California and EniChem Synthesis in Milan) eventhough cubane and its derivatives remain expensive to purchase.