Synthesis and coordination chemistry of aminophosphine derivatives of adenine

Two aminophoshine derivates of adenine N-9-(N-2'-dipenylphosphinoaminoethyl)adenine L1 and N-9-(N-2'-diphenylphosphino-N-2'-n-propylaminoethyl)adenine L2 were synthesized. Oxidation of L1 and L2 with H2O2, elemental sulfur or elemental selenium led to the corresponding oxidized products 5-10. Both L1 and L2 behave as monodentate ligands towards late transition metals. Reaction of compound L1 or L2 with [AuCl(tht)], [{RhCl(mu-Cl)(n(5)-C5Me5)}(2)], [{IrCl(mu-Cl)(eta(5)-C5Me5)}(2)], [{Rh(mu-Cl)(cod)}(2)], <LF>[{RuCl(mu-Cl)(eta(3):eta(3)-C10H16)}(2)] and [{RuCl(mu-Cl)(p-(MeC6H4Pr)-Pr-i)}(2)] gave the corresponding "dangling" monodentate complexes 11-20, leaving the adenine ring free for complementary hydrogen bonding. Interaction of L1 and L2 with [MX2(cod)] (M=Pt: X=Cl, Me) in 2:1 molar ratio also gave monodentate complexes 21 and 22. All compounds have been fully characterized by microanalysis, IR, P-31-{H-1} NMR, H-1 NMR and EI/CI/FAB MS spectroscopies H-1-{P-31} NMR, H-1-H-1-COSY or H-1-C-13 correlation experiments were used to confirm the spectral assignments. Four compounds were structurally characterized by crystallographic X-ray analysis.