Efficient Catalytic Synthesis of α,ω-Di(spiro[adamantane2,3′-[1,2,4,5,7]tetroxazocan]-7′-yl)alkanes

An efficient method has been developed for the synthesis of α,ω-di(spiro[adamantane-2,3′[1,2, 4,5,7]tetroxazocan]-7′-yl)alkanes by recyclization of spiro[adamantane-2,3′-[1,2,4,5,7]pentoxocane] with α,ω-diaminoalkanes in THF in the presence of Sm(NO3)3 · 6 H2O as catalyst.