873300-07-3Relevant academic research and scientific papers
Glycosyl iodides are highly efficient donors under neutral conditions
Hadd, Michael J.,Gervay, Jacquelyn
, p. 61 - 69 (1999)
Glycosyl iodides have been prepared and subjected to glycosylation under neutral conditions. The reactions are highly efficient, giving α glycosides even with sterically demanding glycosyl acceptors. Glucosyl iodides react with allyl alcohol slowest and require refluxing conditions. Galactosyl iodides are intermediate in reactivity, providing the allyl glycoside in 3 h at room temperature, whereas glycosylation of fucosyl iodides occurs in less than 1 h under similar conditions. The scope and limitations of the reactions were demonstrated with a variety of acceptors, including an anomeric hydroxyl group, to give trehalose analogs. β-Selective glycosylation of glucosyl iodides, in the absence of C-2 participation, could be achieved by simply changing the solvent from benzene to acetonitrile. Copyright (C) 1999 Elsevier Science Ltd.
Use of allyl, 2-tetrahydrofuryl, and 2-tetrahydropyranyl ethers as useful C3-, C4-, and C5-carbon sources: Palladium-catalyzed allylation of aldehydes
Shimizu, Masamichi,Kimura, Masanari,Tamaru, Yoshinao
, p. 6629 - 6642 (2007/10/03)
Palladium-diethylzinc or palladium-triethylborane catalytically promotes self-allylation of 2-(allyloxy)tetrahydrofurans, 2-(allyloxy)tetrahydropyrans, and their hydroxy derivatives on the rings (ribose, glucose, mannose, deoxyribose, deoxyglucose). All the reactions proceed at room temperature and provide polyhydroxyl products, sharing a structural motif of a homoallyl alcohol, in good to excellent yields with high levels of stereoselectivity. Useful Crunit elongation, which makes the best use of an allyl ether as a protecting group and a nucleophilic allylation agent, is demonstrated. Mechanisms for the umpolung reaction (of an allyl ether into an allylic anion) and stereoselectivity associated with allylation of aldehydes are discussed.
