Dioxomolybdenum(VI) complexes of quadridentate chiral Schiff bases and the crystal and molecular structure of dioxo[(2R)-propane-1,2-diylbis(salicylideneiminato)]molybdenum(VI)

Mononuclear active sites of molybdoenzymes: chemical approaches to structure and reactivity

“…The reasons for the stability of this structural type raise some important issues with regard to bonding in dioxo-Mo(VI) comple:es. 21 has not yet been observed in a Mo02-thiolate complex, although two complexes with Mo02(OR)2(imine)2 coordination units possess analogous stereochemistry (36). The local minimum derived from starting configurations of 22 correspond to a severely distorted octahedral arrangement, with the 0=Mo=O angle (160°) closed down substantially from 180°.…”

Ionic liquid mediated preparation and X-ray crystal structure of [1-methylimidazolium]2[cis-MoO2(salicylato-O1,O2)2]

“…therein). Many of these complexes have also been characterized by single crystal X-ray crystallography (Atovmyan and Sokolova, 1969;Kopwillem, 1972;Piggott et al, 1988;Sorrell et aL, 1986;Gullotti et al, 1981;Villa et al, 1974;Craig et al, 1989;Brian et al., 1988). However, to our knowledge, the structure of the complex anion [cis-MoO2(sal)2]-z is unknown.…”

Synthesis, spectroscopic characterization, thermal studies, catalytic epoxidation and biological activity of chromium and molybdenum hexacarbonyl bound to a novel N2O2 Schiff base

“…The presence of only one azomethine resonance for the complexes (1) and (4) is consistent with the presence of only a-cis isomer in solution. This is because the a-cis isomer possesses a twofold axis which bisects the NACHRACHRAN chain, and therefore the two CHAN protons are expected to be equivalent [49,50]. The b-cis isomer is less symmetrical and compounds with this structure usually give at least two signals in the 1 H NMR spectrum, (Scheme 2).…”

“…The IR spectrum of the chromium complex (2) showed a strong band at 851 cm À1 due to the Cr@O [38]. The molybdenum complex (4) exhibits two absorption bands at 925 and 940 cm À1 , attributed, respectively, to m sym Mo@O and m asym Mo@O of cis-MoO 2 unit [39][40][41][42][43][44].…”