排序方式: 共有22条查询结果,搜索用时 15 毫秒
1.
María Fernanda Martínez-Esperón 《Tetrahedron》2006,62(16):3843-3855
N,N′-aryl- and N,N′-alkyl-buta-1,3-diyne-1,4-ditosylamides have been synthesized for the first time, in good to excellent yields, by copper-catalyzed dimerization of the corresponding N-aryl or N-alkyl tosylynamides. Negishi coupling of N-ethynylzinc tosylamides derivatives with (hetero)aryl iodides in the presence of Pd2dba3 and triphenylphosphine affords N-aryl and N-alkyl arylynamides in yields of up to 90%. Intramolecular [4+2] cycloaddition reactions of N-ethynylphenyl ynamides and arylynamides allow the synthesis of carbazoles and benzannulated and heteroannulated carbazoles in moderate-to-good yields. 相似文献
2.
A new TfOH-mediated reaction of ynamides with nitriles as nucleophiles has been developed. The reaction works efficiently under mild reaction conditions to afford a new class of α-acylaminoenamides readily via the intermediacy of keteniminium ion. The reaction displays generality and a broad substrates scope. Additionally, the α-acylaminoenamides could be transformed to highly substituted pyridine, 4-aminopyrimidine or isoquinoline cores. 相似文献
3.
Palladium-catalyzed highly regioselective synthesis of benzotriazole appended benzosultams by the tandem-cyclization of functionalized ynamides with benzotriazoles has been accomplished. This transformation involves the formation of both CN and CC bonds in a single step. Donor solvents appear to enhance the yields of the products. The methodology is also applicable for the generation of triazole/tetrazole appended benzosultams. 相似文献
4.
Yanshi Zhang 《Tetrahedron letters》2005,46(38):6483-6486
A highly regio- and stereoselective Brønsted acid-catalyzed coupling of ynamides and indoles is described. This process is the equivalent of hydroarylation of ynamides and leads to the efficient syntheses of vinylindoles. Diels-Alder reaction between the vinylindoles and DMAD afforded carbazole derivatives in good yields. 相似文献
5.
《Comptes Rendus Chimie》2017,20(6):648-664
Ynamides have recently evolved as remarkably reactive and versatile building blocks for chemical synthesis. The development of efficient and robust methods for their preparation combined with their recent commercialization have facilitated both the design of an ever-growing number of original methods based on their unique reactivity and their use in other areas such as medicinal chemistry. One crucial aspect of the reactivity of these building blocks is based on their anionic chemistry, which has been extensively studied during the last decade and enabled not only the design and development of remarkably efficient and original reactions but also brought general answers to long-standing problems in organic chemistry and contributed to the emergence of new synthetic paradigms. In this short review, the anionic chemistry of ynamides is overviewed. 相似文献
6.
A novel BF3-promoted [3+2] annulation of azonaphthalenes and ynamides is described.This protocol provides a modular and efficient entry to functionalized amino benzo[e]indole derivatives smoothly. 相似文献
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8.
Ji Young Kim 《Tetrahedron letters》2008,49(11):1745-1749
Using ynamides as one of the reacting components, the Cu-catalyzed three-component reaction of sulfonyl or phosphoryl azides and amines affords α-amino amidines in high yields under mild conditions. Synthetic utility of the produced compounds was demonstrated in the diastereoselective alkylation of α-amino amidines bearing a chiral oxazolidinone moiety. It was also shown that α-amino imidates could be readily prepared by employing alcohols instead of amines. 相似文献
9.
The first synthesis of 2-iodoynamides is described as well as the first [2+2] cycloadditions of ketene with iodo alkynes. 相似文献
10.
Ynamides react with ketenes in [2+2] cycloadditions leading to a variety of substituted 3-aminocyclobut-2-en-1-ones. The ynamides employed in these reactions are readily available via the copper-promoted N-alkynylation of carbamates and sulfonamides with alkynyl bromides and iodides. The scope of the [2+2] cycloaddition with regard to both the ketene and ynamide component is described. 相似文献