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Synthesis of tetrahydroquinolines and quinoline derivatives through the Lewis acid catalysed Povarov reaction: A comparative study between multi step and multi-component methods

Hellel Djamila, Chafaa Fouad, Nacereddine Abdelmalek Khorief

Scientiae Radices

2023

Vol. 2, Iss. 3

295--308

In this work, we have synthesised a new disubstituted tetrahydroquinolines by the Povarov [4+2] cycloaddition reaction between imines derivatives and an electron-rich olefin such as vinyl ethers. These reactions were carried out in the presence of different acid catalysts in its two versions, multi-step reaction starting with imine synthesis and multi-component reaction in which the imine is formed in situ. The reactivity of the cycloaddition reaction is directly attributed to the nature of the reagents, the used synthetic strategy, in which the obtained yield is found in the case of multi-step reactions lower than that in the multi-component reaction one. Additionally, the multi-step reactions are faster kinetically in comparison with that of the multi-component one. The nature of the catalyst directly increases the rate and enhances the yield of the reactions.

Synthesis of7-Substituted 5-Dethia-5-oxacephams via [2+2]Cycloaddition of Chlorosulfonyl Isocyanate to Sugar Vinyl Ethers

Łysek R., Furman B., Kałuża Z., Chmielewski M.

Polish Journal of Chemistry

2000

Vol. 74, nr 1

51-60

Subsequent transformations of adducts consisting in detritylation, tosylation of a terminal hydroxy group and intramolecular alkylation of the nitrogen atom give corresponding tetracyclic 5-oxacephams.

[2+2]Cycloaddition of Chlorosulfonyl Isocyanate to Chiral Vinyl Ethers

Furman B., Kałuża Z., Łysek R., Chmielewski M.

Polish Journal of Chemistry

1999

vol. 73 nr 1

43-54

The asymmetric [2+2]cycloadditions of chlorosulfonyl isocyanate to vinyl ethers derived from sugars and hydroxy acids are presented. The account focuses on various aspects of the cycloaddition and on the transformations of the resulting [2+2]cycloadducts into clavams and 1-oxacephams. In order to rationalize the results of direction and magnitude of [2+2]cycloaddition, the stereochemical models of this reaction are discussed.