Synthesis Notes on Generating Bimetallic 243Am Complexes Using Inherent Lewis Acidity and the TPT Cryptand

Tris(pyridinediimine)bis(tren) (TPT) was employed as a proligand in reactions with 243Am(NO3)3·nH2O in methanol generating several product types consistent with observations from analogous reactions with the lanthanide series. [Am(TPT)][Am(NO3)6] (1) was identified along with Am2(TPTOMe)(NO3)3 (2; TPTOMe = tris(pyridineimine)(tren)(tris(methoxylhemiacetalate))) from a reaction using Am(NO3)3·nH2O. In a second reaction, performed using a modified preparation of Am(NO3)3·nH2O, Am2(TPTOMe)(NO3)3(MeOH) (2·MeOH) was identified, where methanol coordinated to the terminal metal site. These results highlight the challenges of relying on lanthanide surrogates for actinide chemistry, and the 243Am products are consistent with both early- and late-lanthanide-like reactivity.