Protonation of (2-(dimethylamino) ethyl) cyclopentadienyl (CpN) group VI metal carbonyl
anions with acetic acid proceeds at the amine to provide zwitterionic (2-
(dimethylammonium) ethyl) cyclopentadienyltricarbonylmetalates, M (CO) 3 (η5-CpNH)(M=
Cr (1), Mo (2), W (3)). Few zwitterionic organometalates with anionic metal centers and
positive charges that cannot be delocalized have been reported to date. The impact of the
intramolecular charge separation on the structures and reactivity of zwitterionic …

Zwitterionic [(2-(trimethylammonium) ethyl) cyclopentadienyl] tricarbonylmetalates, M (CO) 3
(η5-CpNMe)(M= Cr (7), Mo (8), W (9)), provide useful models to assess intramolecular
through-space electrostatic interactions on the reactivity of formally negatively charged
metals. The C 3 v M (CO) 3 units in these zwitterions appear largely unperturbed by the
tethered 2-(trimethylammonium) ethyl group; neither significant intra-nor intermolecular ion
pairing occurs either in solution or in the solid state. Although the donor ability of the Cp …