Hangman salen platforms containing dibenzofuran scaffolds.
The synthesis of salen ligands bearing two rigid dibenzofuran spacers functionalized with carboxylic acid and benzoic acid groups completes a series of "Hangman" ligands with the acid functionalities differentially extended across the molecular cleft. Stopped-flow studies show that a high-valent metal oxo intermediate is produced at Hangman platforms when H(2)O(2) is employed as a primary oxidant. The activity of this oxo species in promoting the disproportionation of hydrogen peroxide and olefin epoxidations is discussed in the context of the distance between the acid group and the metal center. The chemistry of the Hangman oxo complexes described here provides a roadmap for water-splitting chemistry.
Yang
Jenny Y
JY
Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139, USA.
Liu
Shih-Yuan
SY
Korendovych
Ivan V
IV
Rybak-Akimova
Elena V
EV
Nocera
Daniel G
DG
D000042:Absorption; D001572:Benzofurans / Q000737:chemistry*; D002384:Catalysis; D005029:Ethylenediamines / Q000737:chemistry*; D007700:Kinetics; D008024:Ligands; D011789:Quantum Theory
D001572:Benzofurans; D005029:Ethylenediamines; D008024:Ligands; C023614:dibenzofuran; C011452:disalicylaldehyde ethylenediamine