21235-72-3Relevant academic research and scientific papers
Cobalt-Catalyzed Aerobic Oxidative Cleavage of Alkyl Aldehydes: Synthesis of Ketones, Esters, Amides, and α-Ketoamides
Li, Tingting,Hammond, Gerald B.,Xu, Bo
supporting information, p. 9737 - 9741 (2021/05/31)
A widely applicable approach was developed to synthesize ketones, esters, amides via the oxidative C?C bond cleavage of readily available alkyl aldehydes. Green and abundant molecular oxygen (O2) was used as the oxidant, and base metals (cobalt and copper) were used as the catalysts. This strategy can be extended to the one-pot synthesis of ketones from primary alcohols and α-ketoamides from aldehydes.
Beyond classical reactivity patterns: Hydroformylation of vinyl and allyl arenes to valuable β- And γ-aldehyde intermediates using supramolecular catalysis
Dydio, Pawe?,Detz, Remko J.,De Bruin, Bas,Reek, Joost N. H.
supporting information, p. 8418 - 8429 (2014/06/24)
In this study, we report on properties of a series of rhodium complexes of bisphosphine and bisphosphite L1-L7 ligands, which are equipped with an integral anion binding site (the DIM pocket), and their application in the regioselective hydroformylation of vinyl and allyl arenes bearing an anionic group. In principle, the binding site of the ligand is used to preorganize a substrate molecule through noncovalent interactions with its anionic group to promote otherwise unfavorable reaction pathways. We demonstrate that this strategy allows for unprecedented reversal of selectivity to form otherwise disfavored β-aldehyde products in the hydroformylation of vinyl 2- and 3-carboxyarenes, with chemo- and regioselectivity up to 100%. The catalyst has a wide substrate scope, including the most challenging substrates with internal double bonds. Coordination studies of the catalysts under catalytically relevant conditions reveal the formation of the hydridobiscarbonyl rhodium complexes [Rh(Ln)(CO)2H]. The titration studies confirm that the rhodium complexes can bind anionic species in the DIM binding site of the ligand. Furthermore, kinetic studies and in situ spectroscopic investigations for the most active catalyst give insight into the operational mode of the system, and reveal that the catalytically active species are involved in complex equilibria with unusual dormant (reversibly inactivated) species. In principle, this involves the competitive inhibition of the recognition center by product binding, as well as the inhibition of the metal center via reversible coordination of either a substrate or a product molecule. Despite the inhibition effects, the substrate preorganization gives rise to very high activities and efficiencies (TON > 18‰000 and TOF > 6000 mol mol-1 h-1), which are adequate for commercial applications.
Supramolecular control of selectivity in hydroformylation of vinyl arenes: Easy access to valuable β-aldehyde intermediates
Dydio, Pawel,Reek, Joost N. H.
supporting information, p. 3878 - 3882 (2013/05/09)
Go against the flow! A rationally designed regioselective hydroformylation catalyst, [Rh/L], in which noncovalent ligand-substrate interactions allow the unprecedented reversal of selectivity from the typical α-aldehyde to the otherwise unfavored product β-aldehyde, is reported. This catalytic system opens up novel and sustainable synthetic pathways to important intermediates for the fine-chemicals industry.
Piperidine and tetrahydropyridine derivatives
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, (2008/06/13)
A class of substituted piperidine and tetrahydropyridine derivatives, linked through the 4-position thereof via an alkylene chain to a fused bicyclic heteroaromatic moiety such as indolyl, and further substituted at the 1-position by an optionally substituted alkyl, alkenyl, alkynyl, cycloalkyl-alkyl, aryl-alkyl or heteroaryl-alkyl moiety, are selective agonists of 5-HT1 -like receptors, being potent agonists of the human 5-HT1Dα; receptor subtype whilst processing at least a 10-fold selective affinity for the 5-HT1Dα; receptor subtype relative to the 5-HT1Dβ; subtype; they are therefore useful in the treatment and/or prevention of clinical conditions, in particular migraine and associated disorders, for which a subtype-selective agonist of 5-HT1D receptors is indicated, whilst eliciting fewer side-effects, notably adverse cardiovascular events, than those associated with non-subtype-selective 5-HT1D receptor agonists.
