Synthesis of cyclic enamides by intramolecular cyclization of acetylenic amides
作者:Peter A. Jacobi、Harry L. Brielmann、Sheila I. Hauck
DOI:10.1016/0040-4039(95)00031-7
日期:1995.2
12 of a type useful in the synthesis of naturally occurring chlorins, isobacteriochlorins, and corrins have been prepared by a process involving Nicholas-Schreiber condensation to afford acetylenic amides 13, followed by either n-Bu4NF or LiA1(NHBn)4-catalyzed ring closure.
Synthesis of Di- and Trivalent Carbohydrate Mimetics with Oxepane Substructure by Employing Copper-Catalyzed [3+2] Cycloadditions of Alkynes with Azidooxepanes
作者:Léa Bouché、Hans-Ulrich Reissig
DOI:10.1002/ejoc.201402191
日期:2014.6
efficient copper(II)-catalyzed diazo transfer reaction employing nonafluorobutanesulfonyl azide as nitrogen donor. These azidooxepanes underwent smooth copper(I)-catalyzed [3+2] cycloadditions with alkynes (click reaction) to provide a series of simple triazoles. With dialkynes and a trialkyne, bis- and tristriazoles containing oxepanesubstructures were prepared. Due to the polyhydroxylated end groups
Starting from methyl 2-siloxycyclopropanecarboxylates simple and efficient one-pot procedures are described that lead to beta-cyanoesters and methoxycarbonyl-substituted terminal alkynes. The prepared functionalized alkynes were subjected to typical transformations such as [3+2] cycloaddition providing triazole derivatives, Sonogashira coupling, Au-catalyzed hydrophosphorylation or a copper-catalyzed coupling of methyl diazoacetate furnishing alkyne 14 and allene derivative 15. The Pauson-Khand reaction of the enyne 4c afforded a diastereomeric mixture of methyl 5-oxohexahydropentalen-2-carboxylate 16 in moderate yield.
Zur Kenntnis des Kohlenstoffringes. 80. Mitteilung [1]. 1,1,6,6-Tetramethyl-cyclodecan und seine Derivate
作者:C. Cordes、V. Prelog、E. Troxler、H. H. Westen
DOI:10.1002/hlca.19680510722
日期:1968.10.31
1,1,6,6-Tetramethyl-cyclodecane and various of its derivatives have been synthesized. The influence of geminal methyl groups on the properties of cyclodecane derivatives, especially on their n.m.r. spectra, has been investigated.