73500-07-9Relevant articles and documents
Protecting-Group-Free Site-Selective Reactions in a Metal-Organic Framework Reaction Vessel
Huxley, Michael. T.,Burgun, Alexandre,Ghodrati, Hanieh,Coghlan, Campbell J.,Lemieux, Anthony,Champness, Neil R.,Huang, David M.,Doonan, Christian J.,Sumby, Christopher J.
, p. 6416 - 6425 (2018)
Site-selective organic transformations are commonly required in the synthesis of complex molecules. By employing a bespoke metal-organic framework (MOF, 1·[Mn(CO)3N3]), in which coordinated azide anions are precisely positioned within 1D channels, we present a strategy for the site-selective transformation of dialkynes into alkyne-functionalized triazoles. As an illustration of this approach, 1,7-octadiyne-3,6-dione stoichiometrically furnishes the mono- click product N-methyl-4-hex-5′-ynl-1′,4′-dione-1,2,3-triazole with only trace bis-triazole side-product. Stepwise insights into conversions of the MOF reaction vessel were obtained by X-ray crystallography, demonstrating that the reactive sites are isolated from one another. Single-crystal to single-crystal transformations of the Mn(I)-metalated material 1·[Mn(CO)3(H2O)]Br to the corresponding azide species 1·[Mn(CO)3N3] with sodium azide, followed by a series of [3+2] azide-alkyne cycloaddition reactions, are reported. The final liberation of the click products from the porous material is achieved by N-alkylation with MeBr, which regenerates starting MOF 1·[Mn(CO)3(H2O)]Br and releases the organic products, as characterized by NMR spectroscopy and mass spectrometry. Once the dialkyne length exceeds the azide separation, site selectivity is lost, confirming the critical importance of isolated azide moieties for this strategy. We postulate that carefully designed MOFs can act as physical protecting groups to facilitate other site-selective and chemoselective transformations.
Addition du Methylazide aux Olefines Portant une Double Substitution Activante Geminee. Etude de la Stabilite Thermique des Triazol-1,2,3-inees Obtenues
Hetet, G. Le,Danion-Bougot, R.,Carrie, R.
, p. 259 - 272 (2007/10/03)
Methylazide reacts with alkenes bearing two electron-withdrawing substituents on the same sp2 carbone and leads to corresponding 1,2,3-triazolines with these substituents in 4 position.Thermolysis of these 1,2,3-triazolines give cycloreversion (alkene + methylazide) and aziridines after extrusion of nitrigen.In the conditions of the thermolysis, aziridine carbone-carbone bond breaks, leading to azomethine ylids that are trapped with alkenes and give pyrrolidines.
