Search results for "variable temperature NMR"

Cis- and trans molybdenum oxo complexes of a prochiral tetradentate aminophenolate ligand : Synthesis, characterization and oxotransfer activity

2020

Abstract Reaction of [MoO2Cl2(dmso)2] with the tetradentate O2N2 donor ligand papy [H2papy = N-(2-hydroxybenzyl)-N-(2-picolyl)glycine] leads to formation of the dioxomolybdenum(VI) complex [MoO2(papy)] (1) as a mixture of cis and trans isomers. Recrystallization from methanol furnishes solid cis-1, whereas the use of a dichloromethane-hexane mixture allows for the isolation of the trans-1 isomer. Both isomers have been structurally characterized by X-ray crystallography and the energy difference between the isomeric pair has been investigated by electronic structure calculations. Optimization of two configurational isomers in the gas phase predicts the trans isomer to lie 2.5 kcal/mol lower…