Repozytorium
Wyszukaj
Kolekcje
Inne
Synthesis and spectroscopic (1H NMR, ESR) characterization of new aryloxy-Mn(II) complexes: steric control over O-vs. phenyl-pi-coordination of ArO- ligands ArO-=C6H5O-, 4-methyl-C6H4O-, 3,5-dimethyl-C6H3O-, 2,6-di-tert-butyl-C6H3O-, 2,6-dimethyl-C6H3O-) to the "Mn(II)Cp" moiety, and their reactivity with carbon dioxide.
Autorzy
Rok wydania
2001
Czasopismo
Numer woluminu
79
Strony
570-577
DOI
10.1139/v01-013
Kolekcja
Język
Angielski
Typ publikacji
Artykuł
The coordination chemistry of phenoxide ligands, such as C6H5O–, 4-(CH3)-C6H4O–, 3,5-(CH3)2-C6H3O–, 2,6-(tert-butyl)2-C6H3O–, 2,6-(CH3)2-C6H3O–, to Mn(II) has been investigated because of the possible implication of Mn(II)–phenoxide complexes as intermediates in the phenylphosphate carboxylase enzyme, a protein which catalyses the selective carboxylation of phenylphosphate to 4-OH-benzoic acid using CO2. We report here the synthesis and characterization of [CpMn(µ-OAr)(THF)]2 (ArO = C6H5O–, 4-(CH3)-C6H4O–, 3,5-(CH3)2-C6H3O–, 2,6-(CH3)2-C6H3O–) and [CpMn(η5-ArO)] (ArO = 2,6-(tert-butyl)2-C6H3O– and 2,6-(CH3)2-C6H3O–) complexes, the first examples of mixed-sandwich complexes with Cp and phenate as π-ligands. The latter bear the 2,6-substituted phenoxide π-coordinated to the [Mn(Cp)]+ moiety. The different mode of bonding of the phenoxide ligands to Mn(II), substantiated by 1H NMR and electron spin resonance (ESR) spectroscopy, is controlled by the steric hindrance of substituents at the 2- and 6-position. The reactivity of the π-bonded ligand towards CO2 is also reported as a quite rare example of nucleophilic attack at the cumulene by the ring-carbon of the phenoxide, which is driven by electron density localization at the 4-position generated upon π-coordination to Mn(II).Key words: Mn(II)-complexes, phenoxide ligands, 1H NMR spectroscopy, ESR spectroscopy, reaction with carbon dioxide.
Adres publiczny
Podobne publikacje
Copper complexes with N-allylisoquinolinium halides: synthesis and crystal structures of [C9H7N(C3H5)]2CuIICl2.86Br1.14, [C9H7N(C3H5)CuIBr2]·H2O, and [C9H7N(C3H5)CuIbr2].
Pavlyuk A. V., Kinzhybalo Vasyl V., Lis Tadeusz, Mys’kiv M. G.
Vanadium phenoxide complexes with oxide, nitride or hydrazide co-ligands: preparation and crystal structures of [V(OC6H3Pri2-2,6) 3NLi(C4H8O) 3], [{VO2(OC6H3Pri2-2,6) 2}2{μ-Li(C4H8O) 2}2] and [V(NNMe2)(OC6H3Pri2-2,6) 3].
Henderson R. A., Janas Zofia, Jerzykiewicz Lucjan B., Richards Raymond L., Sobota Piotr
TiIV and MoV complexes with diesters. The crystal structure of [o-C6H4(CO2CH2CH2Ph)2Cl4Ti],[C2O4(CH2CH2Ph)2Cl4Ti] and [o-C6H4(CO2Et)2Cl3MoO]·C6H6.
Sobota Piotr, Szafert Sławomir, Utko Józef, Lis Tadeusz