27895-61-0Relevant academic research and scientific papers
Synthesis of Cyclic N-Hydroxylated Ureas and Oxazolidinone Oximes Enabled by Chemoselective Iodine(III)-Mediated Radical or Cationic Cyclizations of Unsaturated N-Alkoxyureas
Peilleron, Laure,Retailleau, Pascal,Cariou, Kevin
, p. 5160 - 5169 (2019)
In this study we describe the reactivity of unsaturated N-alkoxyureas in the presence of different combinations of a hypervalent iodine(III) reagent and a bromide source or TEMPO. Three complementary cyclizations can be achieved depending on the reaction conditions. On the one hand, PIFA with pyridinium bromide leads to an oxybromination reaction. On the other hand, bis(tert-butylcarbonyloxy)iodobenzene with tetrabutylammonium bromide or TEMPO triggers aminobromination or aminooxyamination reactions, respectively. Control experiments showed that the three reactions proceed through distinct mechanisms: the first process is ionic while the other two follow a radical manifold. (Figure presented.).
Sequential Metal-Free Thermal 1,3-Dipolar Cycloaddition of Unactivated Azomethine Ylides
Selva, Verónica,Selva, Elisabet,Merino, Pedro,Nájera, Carmen,Sansano, José M.
supporting information, p. 3522 - 3526 (2018/06/26)
The thermal 1,3-dipolar cycloaddition of unactivated azomethine ylides derived from allylamine and aromatic or heteroaromatic aldehydes with maleimides and 1,1- and 1,2-bis(phenylsulfonyl)ethylene affords endo-2,5-trans cycloadducts in moderate to good yi
Imino glycals via ruthenium-catalyzed RCM and isomerization
Schmidt, Bernd,Hauke, Sylvia,Muehlenberg, Nino
, p. 1648 - 1658 (2014/06/23)
N-Allyl-N-homoallylamines were converted in one step into cyclic enamides via a ruthenium-catalyzed assisted tandem catalytic ring-closing metathesis-isomerization sequence. The sequence relies on the in situ transformation of a metathesis active Ru-carbene into an isomerization active Ru-hydride by addition of hydroxide as a chemical trigger.
Multicomponent, Mannich-type assembly process for generating novel, biologically-active 2-arylpiperidines and derivatives
Hardy, Simon,Martin, Stephen F.
, p. 7142 - 7157 (2017/09/12)
A multicomponent, Mannich-type assembly process commencing with commercially available bromobenzaldehydes was sequenced with [3+2] dipolar cycloaddition reactions involving nitrones and azomethine ylides to generate collections of fused, bicyclic scaffolds based on the 2-arylpiperidine subunit. Use of the 4-pentenoyl group, which served both as an activator in the Mannich-type reaction and a readily-cleaved amine protecting group, allowed sub-libraries to be prepared through piperidine N-functionalization and cross-coupling of the aryl bromide. A number of these derivatives displayed biological activities that had not previously been associated with this substructure. Methods were also developed that allowed rapid conversion of these scaffolds to novel, polycyclic dihydroquinazolin-2-ones, 2-imino-1,3-benzothiazinanes, dihydroisoquinolin-3-ones, and bridged tetrahydroquinolines.
Synthesis of nitrogen-containing heterocycles via ring-closing ene-ene and ene-yne metathesis reactions: An easy access to 1- and 2-benzazepine scaffolds and five- and six-membered lactams
Benedetti, Erica,Lomazzi, Michela,Tibiletti, Francesco,Palmisano, Giovanni,Penoni, Andrea,Goddard, Jean-Philippe,Fensterbank, Louis,Malacria, Max
supporting information, p. 3523 - 3533,11 (2012/12/12)
Novel regioselective ring closing ene-yne metathesis provided an efficient access to different substituted 1-benzazepine scaffolds. The reported synthetic approach could also be used as a powerful tool for the selective formation of a highly functionaliza
Multicomponent assembly and diversification of novel heterocyclic scaffolds derived from 2-arylpiperidines
Hardy, Simon,Martin, Stephen F.
supporting information; experimental part, p. 3102 - 3105 (2011/08/10)
A collection of structurally diverse, polyheterocyclic scaffolds comprising a 2-arylpiperidine subunit were synthesized using a Mannich-type multicomponent assembly process, followed by appropriately sequenced ring-forming reactions. An improved procedure
