Synthesis of tritiated diborane and cryptand [2.2.2]

In order to provide a method for in vivo and in vitro detection of cryptand [2.2.2], tritiated cryptand was synthesized by reduction of appropriate bicyclic diamide with tritiated diborane. As part of this synthesis, tritiated diborane was synthesized by the reaction of tritiated sodium borohydride with boron trifluoride etherate and trapped in dry THF. This is a potentially useful agent for selective tritiation of molecules with functional groups which are prone to electrophilic attack.