20894-11-5Relevant articles and documents
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Fishman,Zuffanti
, p. 4466 (1951)
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Synthesis of new chiral macrocycles-based glycolipids and its application in asymmetric Michael addition
Sabah, Karem J.,Zahid, N. Idayu,Hashim, Rauzah
, p. 2653 - 2667 (2021/03/19)
A series of new mix aza- and thia-macrocyclic glycolipids (9, 10, 16 and 17) have been synthesized and their enantiomeric selectivity was studied. The synthesis of the macrocycles involved a simple protection of two hydroxyl groups of the glycolipids followed by building up the mix-heteroatom macrocyclic in simple sequences. The macrocycles and previously investigated analogues (18, 19, 20 and 21) have been applied as phase transfer catalysts in the enantioselective Michael addition of 2-nitropropane to chalcone and showed good-to-excellent enantiomer excess (ee). Among the catalysts, the galactose aza-crown ether-based glycolipid 21 proved to be the most effective with 90% ee. Graphic abstract: [Figure not available: see fulltext.]
Epi-cinchona based thiourea organocatalyst family as an efficient asymmetric Michael addition promoter: Enantioselective conjugate addition of nitroalkanes to chalcones and α,β-unsaturated N-acylpyrroles
Vakulya, Benedek,Varga, Szilard,Soos, Tibor
, p. 3475 - 3480 (2008/09/20)
(Chemical Equation Presented) A small set of easily available epi-cinchona based thiourea organocatalysts have been synthesized and tested in enantioselective Michael addition of nitroalkanes to chalcones. These bifunctional catalyst systems promoted the
Henry reaction and 1,4-addition of nitroalkanes to α,β- unsaturated carbonyl compounds under the influence of MS 4 A in DMSO
Oriyama, Takeshi,Aoyagi, Masaru,Iwanami, Katsuyuki
, p. 612 - 613 (2008/02/07)
In the presence of MS 4 A in DMSO (dimethyl sulfoxide), Henry reaction with various carbonyl compounds and nitroalkanes proceeded smoothly to give the corresponding β-nitroalcohol without a base catalyst. Moreover, 1,4-additon of nitroalkane to α,β-unsaturated ketones was also performed in DMSO. Copyright