497-03-0Relevant articles and documents
Rhodium-Catalyzed Regioselective Hydroformylation of Alkynes to α,β-Unsaturated Aldehydes Using Formic Acid
Fan, Chao,Hou, Jing,Chen, Yu-Jia,Ding, Kui-Ling,Zhou, Qi-Lin
supporting information, p. 2074 - 2077 (2021/04/05)
A rhodium-catalyzed hydroformylation of alkynes with formic acid was developed. The method provides α,β-unsaturated aldehydes in high yield and E-selectivity without the need to handle toxic CO gas.
Selective palladium-catalyzed hydroformylation of alkynes to α,β-Unsaturated Aldehydes
Fang, Xianjie,Zhang, Min,Jackstell, Ralf,Beller, Matthias
, p. 4645 - 4649 (2013/05/22)
Atom-efficient: A selective palladium catalyst system is used for the hydroformylation of alkynes (see picture). In this syngas reaction, various alkynes were smoothly transformed to synthetically interesting α,β-unsaturated aldehydes in good yields with high regio- and stereoselectivity. Copyright
Rhodium-catalyzed hydroformylation of alkynes employing a self-assembling ligand system
Agabekov, Vladislav,Seiche, Wolfgang,Breit, Bernhard
, p. 2418 - 2422 (2013/07/11)
Hydroformylation of alkynes is an underdeveloped atom-economic and redox-neutral method to prepare enals. Applying a new electron poor self-assembling ligand system provides the first general rhodium-catalyst for the chemo- and stereoselective hydroformylation of dialkyl- as well as diaryl-substituted alkynes to furnish enals in excellent chemo- and stereoselectivity.
Neutral nazarov-type cyclization catalyzed by palladium(0)
Shimada, Naoyuki,Stewart, Craig,Bow, William F.,Jolit, Anais,Wong, Kahoano,Zhou, Zhe,Tius, Marcus A.
supporting information; experimental part, p. 5727 - 5729 (2012/08/07)
Joining the circle: The first Pd0 catalyzed Nazarov-type cyclization of diketoesters (see scheme) proceeds in 70 % to 95 % yield under strictly neutral pH conditions. Aryl substitution of the diketoesters is not required, so the reaction shows great versatility and can also proceed with aliphatic substrates. Copyright
Accessing the structural diversity of pyridone alkaloids: Concise total synthesis of rac-citridone A
Fotiadou, Anna D.,Zografos, Alexandros L.
, p. 4592 - 4595 (2011/10/17)
A unique route to the structural diversity of pyridone alkaloids is described based on the concept of a common synthetic strategy. Three different core structure analogues corresponding to akanthomycin, septoriamycin A, and citridone A have been prepared by using a highly selective and novel carbocyclization reaction.
Palladium/di-1-adamantyl-n-butylphosphine-catalyzed reductive carbonylation of aryl and vinyl halides
Brennführer, Anne,Neumann, Helfried,Klaus, Stefan,Riermeier, Thomas,Almena, Juan,Beller, Matthias
, p. 6252 - 6258 (2008/02/04)
A general and efficient palladium-catalyzed reductive carbonylation with low catalyst loadings (0.5 mol % Pd or below) has been developed. The formylation of aryl and heteroaryl bromides proceeds smoothly in the presence of palladium/di-1-adamantyl-n-butylphosphine at ambient pressure of synthesis gas to afford the corresponding aromatic aldehydes in good yields and excellent selectivity. In addition, vinyl halides react under similar conditions to form α,β-unsaturated aldehydes in good yield.
Directed regio- and stereoselective hydroformylation of mono- and 1,3-disubstituted allylic alcohols: A catalytic approach to the anti-aldol-retron
Breit, Bernhard,Demel, Peter,Gebert, Antje
, p. 114 - 115 (2007/10/03)
Regioselective and diastereoselective hydroformylation of mono- and 1,3-disubstituted allylic alcohol o-DPPB esters is described. The products represent synthetically important anti-aldol retrons.
Isomerization of epoxyalkenes to 2,5-dihydrofurans
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Example 330, (2008/06/13)
Disclosed are processes for the isomerization of epoxyalkenes to dihydrofurans by contacting an epoxyalkene with a catalyst comprising a quaternary organic onium iodide compounds, optionally deposited on a non-acidic support and/or in combination with a Lewis acid co-catalyst. The catalyst may comprise a supported catalyst, an unsupported catalyst or a solution of the catalytically-active components in an inert, organic solvent.
Structure-cytoprotective activity relationship of simple molecules containing an α,β-unsaturated carbonyl system
Rodríguez, Ana M.,Enriz, Ricardo D.,Santagata, Luis N.,Jáuregui, Esteban A.,Pestchanker, Mauricio J.,Giordano, Oscar S.
, p. 1827 - 1834 (2007/10/03)
In previous reports we attributed the cytoprotective activity of several sesquiterpene lactones to the presence of a nonhindered electrophilic acceptor in their structure. We suggested that the mechanism of protection would be, at least in part, mediated through a reaction between the electrophilic acceptor and the sulfhydryl-containing groups of the mucosa. We report here the gastric cytoprotective effect of simple molecules containing an α,β-unsaturated carbonyl group. In the present paper, we undertake the study of molecular accessibility and molecular shape, in addition to conformational, electronic, and steric factors. Our results helped to establish two important facts connecting chemical structure with cytoprotective effect. Firstly, an adequate molecular accessibility appears to be necessary to produce the biological response, and secondly, the α,β- unsaturated carbonyl system has to be included in a cyclic structure or, at least, in the proximity of a cyclic system.
