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Updated: Jul 7, 2026
Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
Synthesis and structure of two tetranuclear osmium carbonyl isotopomers: a crystallographic isotope effect
John P Canal1, Michael Jennings, Glenn P A Yap
1Department of Chemistry, Simon Fraser University, Burnaby, British Columbia, CanadaV5A 1S6. jcanal@sfu.ca.
Abstract:
A synthetic route to [Os4(mu-H)(mu-OH)(mu-CO)(CO)12] ( 1) has been devised through the activation of [Os4(CO)14] with Me3NO. The pyrolysis and photolysis of the reactant in the presence of a trace amount of water produces 1 in low yield. The solid-state structure of [Os4(mu-H)(mu-OH)(mu-CO)(CO)12 x H2O] (1 x H2O) reveals a butterfly Os4 skeleton with bridging H, OH and CO ligands as well as hydrogen-bonded molecules of water in the crystal lattice. A low-temperature 13C{1H} NMR spectroscopic study revealed a merry-go-round exchange of CO ligands around the Os3 plane containing the asymmetric bridging CO. The exposure of 1 x H2O to D2O yielded [Os4(mu-H)(mu-OD)(mu-CO)(CO)12]2. Although the solid-state, intramolecular structure of 2 closely matched that of 1 x H2O, the intermolecular structure did not: its crystal lattice contained no water of crystallization, a previously unreported crystallographic isotope effect.
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