Regiospecific synthesis of 3-(2,6-dihydroxyphenyl)phthalides: application to the synthesis of isopestacin and cryphonectric acid
作者:Dipakranjan Mal、Pallab Pahari、Saroj Ranjan De
DOI:10.1016/j.tet.2007.08.048
日期:2007.11
DBU catalyzedcondensation of phthalaldehydic acids and 1,3-diketones has been developed to be a general method for the synthesis of 3-substituted phthalides. This method, in combination with mercuricacetate mediated oxidative aromatization has been utilized for the regiospecific synthesis of isopestacin (9) and cryphonectric acid (10).
Sulfonic Acid-Catalyzed Autoxidative Carbon-Carbon Coupling Reaction under Elevated Partial Pressure of Oxygen
作者:Áron Pintér、Martin Klussmann
DOI:10.1002/adsc.201100563
日期:2012.3
reactivity at ambient pressure. The benzylicCHbonds of xanthene, acridanes, isochromane and related heterocycles could be functionalized with nucleophiles including ketones, 1,3‐dicarbonyl compounds and aldehydes. Electron‐rich arenes could be utilized as nucleophiles at elevated temperatures. The reactions are believed to proceed via autoxidation of the benzylicCHbonds to the hydroperoxides and subsequent
A jackpot C–H activation protocol using simple ruthenium catalyst in deep eutectic solvents
作者:Nerea González-Gallardo、Beatriz Saavedra、Gabriela Guillena、Diego J. Ramón
DOI:10.1039/d2gc01177h
日期:——
and commercially available ruthenium catalyst was used along with different DESs under different reaction conditions. This methodology was compatible with the use of either internal or external oxidant (oxygen from air) using a catalytical amount of copper salts for the last case. Different functional directing groups were well tolerated obtaining promising results, that were comparable and even better
Hamburger, Monatshefte fur Chemie, 1898, vol. 19, p. 432
作者:Hamburger
DOI:——
日期:——
Expeditious synthesis of 3,4-dihydroisocoumarins and phthalides using the Heck–Matsuda reaction
作者:Eduardo T. da Penha、José Augusto Forni、André F.P. Biajoli、Carlos Roque D. Correia
DOI:10.1016/j.tetlet.2011.09.014
日期:2011.11
Several 3,4-dihydroisocoumarins and phthalides were synthesized by an effective Heck-Matsuda reaction involving an ortho carboxybenzenediazonium salt with a series of styrenes bearing electron donating and electron withdrawing groups, methylvinyl ketone, and methyl acrylate. The reaction was carried out in an open-flask with 1% mol of palladium acetate in aqueous ethanol at similar to 80 degrees C, giving the correspondent 3-aryl-3,4-dihydroisocoumarins and phthalides with good overall yields. The electronic nature of the group attached to the olefin is a key feature for the regioselectivity of the cyclization step. (C) 2011 Elsevier Ltd. All rights reserved.