127722-74-1Relevant academic research and scientific papers
Enhanced Catalytic Activity of Iridium(III) Complexes by Facile Modification of C,N-Bidentate Chelating Pyridylideneamide Ligands
Navarro, Miquel,Smith, Christene A.,Albrecht, Martin
, p. 11688 - 11701 (2017)
A set of aryl-substituted pyridylideneamide (PYA) ligands with variable donor properties owing to a pronounced zwitterionic and a neutral diene-type resonance structure were used as electronically flexible ligands at a pentamethylcyclopentadienyl (Cp) iridium center. The straightforward synthesis of this type of ligand allows for an easy incorporation of donor substituents such as methoxy groups in different positions of the phenyl ring of the C,N-bidentate chelating PYA. These modifications considerably enhance the catalytic activity of the coordinated iridium center toward the catalytic aerobic transfer hydrogenation of carbonyls and imines as well as the hydrosilylation of phenylacetylene. Moreover, these PYA iridium complexes catalyze the base-free transfer hydrogenation of aldehydes, and to a lesser extent also of ketones. Under standard transfer hydrogenation conditions including base, aldehydes are rapidly oxidized to carboxylic acids rather than reduced to the corresponding alcohol, as is observed under base-free conditions.
Donor-Flexible Nitrogen Ligands for Efficient Iridium-Catalyzed Water Oxidation Catalysis
Navarro, Miquel,Li, Mo,Müller-Bunz, Helge,Bernhard, Stefan,Albrecht, Martin
, p. 6740 - 6745 (2016)
A pyridylideneamide ligand with variable donor properties owing to a pronounced zwitterionic and a neutral diene-type resonance structure was used as a dynamic ligand at a Cp? iridium center to facilitate water oxidation catalysis, a reaction that requires the stabilization of a variety of different iridium oxidation states and that is key for developing an efficient solar fuel device. The ligand imparts high activity (nearly three-fold increase of turnover frequency compared to benchmark systems), and exceptionally high turnover numbers, which indicate a robust catalytic cycle and little catalyst degradation.
Non-acidic anti-inflammatory compounds: activity of N-(4,6-dimethyl-2-pyridinyl) benzamides and derivatives
Robert-Piessard, Sylvie,Le Baut, Guillaume,Courant, Jacqueline,Brion, Jean-Daniel,Sparfel, Louis,et al.
, p. 9 - 19 (2007/10/02)
The inhibition of the carragenin-induced rat-paw edema by previously synthesized N-(4,6-dimethyl)-2-pyridinyl) benzamides was evaluated.Amoung the 29 tested compounds, secondary benzamides 1, 12 and tertiary benzamide 60 exhibited a significant anti-inflammatory activity.It prompted us to envision a pharmacomodulation in this series by structural modifications on the homocycle, the amide function and the heterocycle.Although benzamide 38, acetamide 50 and benzylamine 56 elicited marked inhibitory activity, none was more active than N-(4,6-dimethyl-2-pyridinyl) benzamide 1. The mechanism of the anti-inflammatory action of 1 was investigated.The results showed that this molecule reduced eicosanoid biosynthesis but was unable to reduce cyclooxygenase or lipoxygenase activities.Although it did not directly block phospholipase activity, however, an inhibitory process at this level is likely.
