- A metalation strategy for the construction of functionalized naphthalenes: The first synthesis of guieranone A
-
The first synthesis of the natural product guieranone A is described, demonstrating a one-pot procedure for the synthesis of protected-1,3,6,8- tetraoxygenated naphthalenes and a subsequent directed metalation synthesis of 2-keto naphthalenes.
- McCulloch, Malcolm W.B.,Barrow, Russell A.
-
-
Read Online
- A peri-cyclised naphthalene dimer: Synthesis and properties of an unusual Vilsmeier-Haack product of 1,3,6,8-tetramethoxynaphthalene
-
An unusual peri-dimerised product was obtained when subjecting 1,3,6,8-tetramethoxynaphthalene to Vilsmeier-Haack reaction conditions (POCl3/DMF). The formation of this peri-dimerised naphthalene product suggests that 1,3,6,8-tetramethoxynaphthalene has comparable reactivity to that of Proton Sponge [1,8-bis(dimethylamino)naphthalene]. The octamethoxy peri-dimer was characterised using NMR spectroscopy, mass spectrometry, UV/Vis spectroscopy, Raman spectroscopy, electrochemistry, X-ray crystallography and DFT calculations. The one-electron oxidation of the peri-dimerised naphthalene compound yielded a radical cation that was studied by EPR spectroscopy and UV/Vis spectroscopy at low temperatures. The experimental observations were confirmed by DFT calculations. The Vilsmeier-Haack reaction (POCl 3/DMF) of 1,3,6,8-tetramethoxynaphthalene gave an unusual peri-cyclised dimer as well as the 1-naphthaldehyde. The dimer is a potent donor molecule. Copyright
- Pittelkow, Michael,Nielsen, Christian B.,Brock-Nannestad, Theis,Schau-Magnussen, Magnus,Christensen, Jrn B.
-
-
Read Online
- Mild aromatic palladium-catalyzed protodecarboxylation: Kinetic assessment of the decarboxylative palladation and the protodepalladation steps
-
Mechanism studies of a mild palladium-catalyzed decarboxylation of aromatic carboxylic acids are described. In particular, reaction orders and activation parameters for the two stages of the transformation were determined. These studies guided development of a catalytic system capable of turnover. Further evidence reinforces that the second stage, protonation of the arylpalladium intermediate, is the rate-determining step of the reaction. The first step, decarboxylative palladation, is proposed to occur through an intramolecular electrophilic palladation pathway, which is supported by computational and mechanism studies. In contrast to the reverse reaction (C-H insertion), the data support an electrophilic aromatic substitution mechanism involving a stepwise intramolecular protonation sequence for the protodepalladation portion of the reaction.
- Dickstein, Joshua S.,Curto, John M.,Gutierrez, Osvaldo,Mulrooney, Carol A.,Kozlowski, Marisa C.
-
p. 4744 - 4761
(2013/07/11)
-
- Development of a catalytic aromatic decarboxylation reaction
-
A palladium-catalyzed aromatic decarboxylation reaction has been developed. With electron-rich aromatic adds, the reaction proceeds efficiently under fairly mild conditions in good yields. The method was useful with complex functionalized substrates containing hindered carboxylic adds.
- Dickstein, Joshua S.,Mulrooney, Carol A.,O'Brien, Erin M.,Morgan, Barbara J.,Kozlowski, Marisa C.
-
p. 2441 - 2444
(2008/02/05)
-
- Carbocations in action. Design, synthesis, and evaluation of a highly acid-sensitive naphthalene-based backbone amide linker for solid-phase synthesis
-
(Diagram presented) The design, synthesis, and properties of an extremely acid-labile backbone amide linker based on a regiospecifically substituted tetraalkoxy naphthaldehyde core are presented. This handle enables cleavage of peptide backbone amides (se
- Pittelkow, Michael,Boas, Ulrik,Christensen, Jorn B.
-
p. 5817 - 5820
(2007/10/03)
-