69248-34-6Relevant academic research and scientific papers
Direct Stereoselective Installation of Alkyl Fragments at the β-Carbon of Enals via Excited Iminium Ion Catalysis
Verrier, Charlie,Alandini, Nurtalya,Pezzetta, Cristofer,Moliterno, Mauro,Buzzetti, Luca,Hepburn, Hamish B.,Vega-Pe?aloza, Alberto,Silvi, Mattia,Melchiorre, Paolo
, p. 1062 - 1066 (2018)
The direct introduction of sp3 carbon fragments at the β position of α,β-unsaturated aldehydes is greatly complicated by competing 1,2-addition manifolds. Previous catalytic enantioselective conjugate addition methods, based on the use of organometallic reagents or ground-state iminium ion activation, could not provide general and efficient solutions. We report herein that, by turning them into strong oxidants, visible light excitation of chiral iminium ions triggers a stereocontrolled radical pathway that exclusively affords highly enantioenriched β-substituted aldehydes bearing a variety of alkyl fragments.
NITROGENOUS CYCLIC COMPOUNDS AND PHARMACEUTICAL COMPOSITIONS CONTAINING THE SAME
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, (2008/06/13)
The present invention provides a novel compound having a superior calcium antagonism, in particular, a neuron-selective calcium antagonism. Namely, it provides a compound represented by the following formula, a salt thereof or a hydrate of them. In the formula, Ar indicates an optionally substituted 5- to 14-membered aromatic ring etc.; the ring A indicates any one ring selected from a piperazine, a homopiperazine, a piperidine and the like; the ring B indicates an optionally substituted C3-14 hydrocarbon ring etc.; E indicates a single bond, a group represented by the formula -CO-, etc.; X indicates a single bond, an oxygen atom etc.; R1 indicates a hydrogen atom, a halogen atom, a hydroxyl group etc.; and D1, D2, W1 and W2 are the same as or different from each other and each represents a single bond or an optionally substituted C1-6 alkylene chain.
The effects of in-situ trimethylsilyl chloride on the regioselectivity of the addition of α-alkoxy- and α-alkyl-substituted organocuprates to enals
Linderman, Russel J.,McKenzie, Joyce R.
, p. 31 - 42 (2007/10/02)
The regioselectivity of the addition of α-substituted organocuprates to enals has been examined.The addition of trimethylsilyl chloride to both the enal and cuprate prior to the combination of the reactants improves the regioselectivity and the isolated y
