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Iridium bis(iminoxolene) complexes with 2,6-dibromophenyl substituents can be prepared in four different oxidation states, including a reduced complex with a sodium–iridium bond. 

The bis(iminoxolene) complex (Diso)2IrCl (Diso = N-(2,6-diisopropylphenyl)-4,6-di-tert-butyl-2-imino-o-benzoquinone) is reduced by two equivalents of sodium naphthalenide to give square planar, diamagnetic Na[(Diso)2Ir]. The anionic iridium center acts as a nucleophile to primary and secondary alkyl and allyl halides to give square pyramidal iridium alkyls. Benzoyl chloride reacts to give an iridium benzoyl complex. Organoiridium complexes are also formed by reaction of (Diso)2IrCl with Grignard reagents, and treatment with acetone in the presence of base gives the 1 carbon-bonded enolate complex (Diso)2IrCH2COCH3. The solid-state structures of the primary alkyls show significant inclinations of the iridium-carbon bond away from the twofold axis of the square pyramid, apparently for steric reasons. The relative reactivity of substrates and exclusive formation of (Diso)2Ir(5-hexenyl) from 1-bromo-5-hexene indicates that primary alkyl halides react by an SN2 mechanism. Structural data suggest that the oxidative addition is about 70% metal centered, consistent with nucleophilic behavior that is analogous to that of other square planar group 9 anions. 

Optically active C 2 -symmetric bis(aminophenols) based on ( R )-2,2′-diaminobinaphthyl (BiniqH 4 ) and ( R , R )-2,3-butanediyldianthranilate (BdanH 4 ) have been prepared by condensation of the diamines with 3,5-di- tert -butylcatechol. Group 10 bis(iminosemiquinone) complexes ( R )-(Biniq)M (M = Pd, Pt) and ( C , R , R )-(Bdan)Pd have been prepared by oxidatively metalating the corresponding ligands. In ( R )-(Biniq)M, the C 2 axis passes through the approximate square plane of the bis(iminosemiquinone)metal core, while in ( C , R , R )-(Bdan)Pd the C 2 axis is perpendicular to this plane. In the latter compound, the ( R , R )-butanediyl strap binds selectively over one enantioface of the metal complex in a conformation where the methyl groups are anti to one another. Osmium oxo complexes with the intrinsically chiral OsO(amidophenoxide) 2 chromophore are obtained by metalation of OsO(OCH 2 CH 2 O) 2 with ( R , R )-BdanH 4 . Both the ( A , R , R ) and ( C , R , R ) diastereomers can be observed, with metalation in refluxing toluene selectively giving the latter isomer. The electronic structures of the complexes are illuminated by the circular dichroism spectra, in conjuction with the optical spectra and TDDFT calculations. 

Both pseudo-octahedral and pseudo-square pyramidal bis-iminoxolene complexes trans -(Diso) 2 RuCl 2 and trans -(Diso) 2 Ru(PPh 3 ) are structurally distorted, with the ruthenium atom slipping off the twofold axis of the idealized coordination polyhedra. These distortions take place because they allow or enhance π interactions between ruthenium and the iminoxolene π orbitals.