Structural studies of bis(cyclopentadienyl)molybdenum-amino acid complexes

The crystal structures of molybdocene-amino acid compounds of the type [Cp2MoIV(kappaN,kappaO-AA)](+)Cl(-.)xH(2)O with AA = D-phenylalaninato (x = 1.5), DL-leucinato (x = 2) and DL-valinato (x = 1) have been determined (Cp = eta(5)-C5H5). The compounds feature an almost planar, five-membered chelate ring of the aminocarboxylate moiety (deprotonated amino acid) with the molyb-denum atom. In the phenylalaninato complex pi-stacking between the phenyl rings is found. The complexes were proven kinetically stable at pH < 1 for at least 24 h.