Nucleophile-Catalyzed Additions to Activated Triple Bonds. Protection of Lactams, Imides, and Nucleosides with MocVinyl and Related Groups
Contribuinte(s) |
Universitat de Barcelona |
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Data(s) |
28/05/2014
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Resumo |
Additions of lactams, imides, (S)-4-benzyl-1,3-oxazolidin-2-one, 2-pyridone, pyrimidine-2,4-diones (AZT derivatives), or inosines to the electron-deficient triple bonds of methyl propynoate, tert-butyl propynoate, 3-butyn-2-one, N-propynoylmorpholine, or N-methoxy-N-methylpropynamide in the presence of many potential catalysts were examined. DABCO and, second, DMAP appeared to be the best (highest reaction rates and E/Z ratios), while RuCl3, RuClCp*(PPh3)2, AuCl, AuCl(PPh3), CuI, and Cu2(OTf)2 were incapable of catalyzing such additions. The groups incorporated (for example, the 2-(methoxycarbonyl)ethenyl group that we name MocVinyl) serve as protecting groups for the above-mentioned heterocyclic CONH or CONHCO moieties. Deprotections were accomplished via exchange with good nucleophiles: the 1-dodecanethiolate anion turned out to be the most general and efficient reagent, but in some particular cases other nucleophiles also worked (e.g., MocVinyl-inosines can be cleaved with succinimide anion). Some structural and mechanistic details have been accounted for with the help of DFT and MP2 calculations. |
Identificador | |
Idioma(s) |
eng |
Publicador |
American Chemical Society |
Direitos |
(c) American Chemical Society , 2013 info:eu-repo/semantics/openAccess |
Palavras-Chave | #Síntesi orgànica #Amines #Catalitzadors #Lactames #Nucleòsids #Proves i reactius químics #Organic synthesis #Amines #Catalysts #Lactams #Nucleosides #Chemical tests and reagents |
Tipo |
info:eu-repo/semantics/article info:eu-repo/semantics/acceptedVersion |