AN INERT PROTON COORDINATED INSIDE THE TETRAHEDRAL CAGE [3(6)]ADAMANZANE - SYNTHESIS OF THE INSIDE MONOPROTONATED AMINE 1,5,9,13-TETRAAZATRICYCLO[7.7.3.3(5,13)]DOCOSANE

The reaction of 1,5,9-triazacyclododecane with tris(3-chloropropyl)ami ne affords the inside monoprotonated form of the tricyclic amine 1,5,9 ,13-tetraazatricyclo[7.7.3.3(5,13)]docosane ([3(6)]adamanzane), which was isolated as the bromide salt, [H[3(6)]adz]Br . 0.5H(2)O (27%) and the dithionate salt, [H[3(6)]adz](2)[S2O6] (28%). The tricyclic struct ure of H[3(6)]adz(+) was established by H-1 and C-13 NMR spectroscopy, which shows that the cation in solution has a time-averaged T-d symme try. H[3(6)]adz(+) is unusually inert as to reaction with base. From H -1 NMR measurements it is estimated that the rate constant for the dis sociation the inside coordinated proton of H[3(6)]adz(+) in 0.1 M NaOD is less than 4 x 10(-8) s(-1) at 25 degrees C. In chloroform and in a queous solutions (pH > 2) the dominant form of the cage has all four l one pairs pointing inside the cavity.