Search for: All records

Temperature-dependent metalation of the new hexadentate ligand (tris(5-(pyridin-2-yl)-1 H -pyrrol-2-yl)methane; H 3 TPM) enables the selective synthesis of both mononuclear ( i.e. Na(THF) 4 [Fe(TPM)], kinetic product) and trinuclear ( i.e. Fe 3 (TPM) 2 , thermodynamic product) complexes. Exposure of Na(THF) 4 [Fe(TPM)] to FeCl 2 or ZnCl 2 triggers cluster expansion to generate homo- or heterometallic trinuclear complexes, respectively. The developed approach enables systematic variation of ion content in isostructural metal clusters via programmed assembly. 

The syntheses, structural, and magnetic characterization of three new organometallic Ce complexes stabilized by PyCp 2 2− (PyCp 2 2− = [2,6-(CH 2 C 5 H 3 ) 2 C 5 H 3 N] 2− ) are reported. Complex 1 provides the first example of a crystallographically characterized unsupported Ce–Fe bond in a molecular compound. Results from IR spectroscopy and computational analyses suggest weaker Fe → Ce electron-donation than in a previously reported Dy–Fe bonded species. 

tert‐Butoxide unlocks new reactivity patterns embedded in nitroarenes. Exposure of nitrostilbenes to sodium tert‐butoxide was found to produce N‐hydroxyindoles at room temperature without an additive. Changing the counterion to potassium changed the reaction outcome to yield solely oxindoles through an unprecedented dioxygen‐transfer reaction followed by a 1,2‐phenyl migration. Mechanistic experiments established that these reactions proceed via radical intermediates and suggest that counterion coordination controls whether an oxindole or N‐hydroxyindole product is formed.

 

tert‐Butoxide unlocks new reactivity patterns embedded in nitroarenes. Exposure of nitrostilbenes to sodium tert‐butoxide was found to produce N‐hydroxyindoles at room temperature without an additive. Changing the counterion to potassium changed the reaction outcome to yield solely oxindoles through an unprecedented dioxygen‐transfer reaction followed by a 1,2‐phenyl migration. Mechanistic experiments established that these reactions proceed via radical intermediates and suggest that counterion coordination controls whether an oxindole or N‐hydroxyindole product is formed.