Crystal structures of two unusual, high oxidation state, 16-electron iridabenzenes

Acta Crystallographica Section E: Crystallographic Communications. 2015;71(11):1315-1318 DOI 10.1107/S2056989015018952

 

Journal Homepage

Journal Title: Acta Crystallographica Section E: Crystallographic Communications

ISSN: 2056-9890 (Online)

Publisher: International Union of Crystallography

LCC Subject Category: Science: Chemistry

Country of publisher: United Kingdom

Language of fulltext: English

Full-text formats available: PDF, HTML

 

AUTHORS

Daniel T. Chase (Department of Chemistry & Biochemistry and Materials Science Institute, University of Oregon, Eugene, Oregon 97403-1253, USA)
Lev N. Zakharov (CAMCOR, University of Oregon, 1443 East 13th Avenue, Eugene, Oregon 97403, USA)
Michael M. Haley (Department of Chemistry & Biochemistry and Materials Science Institute, University of Oregon, Eugene, Oregon 97403-1253, USA)

EDITORIAL INFORMATION

Blind peer review

Editorial Board

Instructions for authors

Time From Submission to Publication: 3 weeks

 

Abstract | Full Text

Treatment of carbonyl(1,2-diphenylpenta-1,3-dien-1-yl-5-ylidene)bis(triphenylphosphane)iridium, [IrCO(—C(Ph)=C(Ph)—CH=CH—CH=)(PPh3)2], with either bromine or iodine produced dibromido(1,2-diphenylpenta-1,3-dien-1-yl-5-ylidene)(triphenylphosphine)iridium(III), [IrBr2{—C(Ph)=C(Ph)—CH=CH—CH=}(PPh3)], (I), and (1,2-diphenylpenta-1,3-dien-1-yl-5-ylidene)diiodido(triphenylphosphane)iridium(III), [IrI2{—C(Ph)=C(Ph)—CH=CH—CH=}(PPh3)], (II), respectively, which are two rare examples of 16-electron metallabenzenes. Structural elucidation of (I) and (II) reveals that these isotypic iridabenzenes are unusual, not only in their electron count, but also in their coordination sphere of the IrIII atom where they contain an apparent open coordination site. The crystal structures of (I) and (II) confirm that the molecules are complexes containing five-coordinated IrIII with only one triphenylphosphine group bound to the iridium atom, unambiguously proving that the molecules are indeed 16-electron, high-oxidation-state iridabenzenes. The coordination geometry of the IrIII atom in both structures can be best described as a distorted square pyramid with the P, two Br (or I) and one C atom in the basal plane and another C atom in the apical position.