A process for the hydrogenolysis of 2,4,6,8,10,12-hexabenzyl-2,4,6,8,10,12-hexaazatetracyclo [5.5.0.0?5,9.03,11¿]dodecane ('HBIW') is disclosed in which a quantity of HBIW, cosolvent and a bromine source are placed into a reaction vessel. Acetic anhydride and a substantially water-free palladium catalyst are then rapidly added. The reaction vessel is purged of an atmosphere capable of reacting with hydrogen, and hydrogen is quickly introduced to convert the HBIW to tetraacetyl-dibenzylhexaazaisowurtzitane ('TADB'). The acetic anhydride is added immediately prior to hydrogen introduction so that it does not have time to react with the HBIW to form an acetylated derivative prior to commencement of the desired hydrogenation reaction. The process requires very little palladium catalyst, preferably less than 10 % wt./wt. based on the HBIW substrate. The TADB, precipitated on the palladium hydrogenation catalyst, is subjected to a second hydrogenation step using formic acid solvent in the presence of hydrogen to form tetraacetyldiformylhexaazaisowurtzitane ('TADF').
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