Hydrogenolysis of 2,4,6,8,10,12-Hexabenzyl-2,4,6,8,10,12-Hexaazatetracyclo[5.5.0.05,9.03,11]dodecane

摘要

A process for the hydrogenolysis of 2,4,6,8,10,12-hexabenzyl-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.05,9.03,11]dodecane ("HBIW") is disclosed. In the process, a quantity of HBIW, a cosolvent, and a bromine source are placed into a reaction vessel. Acetic anhydride and a palladium hydrogenolysis catalyst are rapidly added to the reaction vessel. The hydrogenolysis catalyst should be substantially free of water. The reaction vessel is purged of an atmosphere capable of reacting with hydrogen, and hydrogen is quickly introduced into the reaction vessel to convert the HBIW to tetraacetyldibenzylhexaazaisowurtzitane ("TADB"). The acetic anhydride is added immediately prior to hydrogen introduction so that the acetic anhydride 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 hydrogenolysis catalyst, is subjected to a second hydrogenation step using a formic acid solvent in the presence of hydrogen to form tetraacetyldiformylhexaazaisowurtzitane ("TADF").