2-Aminoalkylgold Complexes: The Putative Intermediate in Au-Catalyzed Hydroamination of Alkenes Does Not Protodemetalate.

Au-catalyzed hydroamination proceeds well for alkynes but not alkenes. We report gas-phase binding energies of alkenes and alkynes to a cationic Au center, which indicate that differences in binding are not the origin of the disparate chemical behavior. We further report the synthesis and characterization of 2-aminoalkylgold complexes, which would be the intermediates in a hypothetical Au-catalyzed hydroamination of styrene.

Structure of a push-pull olefin prepared by ynamine hydro-boration with a borandiol ester.

-[()-2-(2-1,3,2-Benzodioxaborol-2-yl)-2-phenyl-ethen-yl]--(propan-2-yl)aniline, CHBNO, contains a C=C bond that is conjugated with a donor and an acceptor group. An analysis that included similar push-pull olefins revealed that bond lengths in their B-C=C-N core units correlate with the perceived acceptor and donor strength of the groups. The two phenyl groups in the mol-ecule are rotated with respect to the plane that contains the BCCN atoms, and are close enough for significant π-stacking.

Theoretical 57Fe Mössbauer spectroscopy for structure elucidation of [Fe] hydrogenase active site intermediates.

[Fe] hydrogenase is a hydrogen activating enzyme that features a monoiron active site, which can be well characterized by Mössbauer spectroscopy. Mössbauer spectra have been measured of the CO and CN(-) inhibited species as well as under turnover conditions [Shima, S. et al.