Ruthenium(III) Chloride Catalyzed Oxidation of Pyrene and 2,7-Disubstitued Pyrenes:  An Efficient, One-Step Synthesis of Pyrene-4,5-diones and Pyrene-4,5,9,10-tetraones

Abstract

Pyrene and 2,7-disubstituted pyrenes have been oxidized with ruthenium(III) chloride (RuCl3) and sodium periodate (NaIO4) under very mild conditions to 4,5-diones or 4,5,9,10-tetraones. Thus, the oxidation has been controlled by varying the amount of oxidant and reaction temperature to proceed exclusively at the pyrene 4- and 5-positions or at the 4-, 5-, 9-, and 10-positions.

Blue-Emitting Butterfly-Shaped 1,3,5,9-Tetraarylpyrenes: Synthesis, Crystal Structures, and Photophysical Properties

“…8 Besides electrophilic substitution of pyrene, Harris showed an efficient, one-step synthetic approach to catalyze the oxidation of the K-region of pyrene using ruthenium chloride. 11 Müllen et. al.…”

An Efficient Approach to the Synthesis of Novel Pyrene-Fused Azaacenes

“…Compound 2 was then oxidized at the K-region using ruthenium chloride based catalysis 13 (Scheme 1). The key intermediate, 1,3-dibromo-7-tert-butylpyrene-4,5,9,10-tetraone 3 was easily prepared by the bromination and successive oxidation in considerable yield.…”

“…H/ 13 C NMR spectra, X-ray crystallographic data, photophysical data, TGA analysis and computational plot. This materials is available free of charge via the Internet at http://pubs.acs.org.…”

Metal compounds with rigid polyaromatic ligands. Catalytic consequences

“…[5][6][7][8] The most widely employed protocols for the synthesis of NHC-based complexes requires the activation of an azolium-based salt. Other commonly used strategies involve the insertion of a metal into the C=C bond of bis(imidazolidin-2-ylidene) olefins [23][24][25] and the use of carbene adducts.…”

“…The first NHC complexes were described by Öfele and Wanzlick in 1968; 2,3 and Herrmann described the first catalytic application of NHC complexes in 1995. 4 Ever since, NHCs have been widely studied from any possible point of view, including their preparation, [5][6][7][8] stability, 9 stereoelectronic properties, [10][11][12] coordination strategies, 8,13,14 and use in homogeneous 15 and asymmetric catalysis, 16,17 and some books 1,[18][19][20] have been entirely devoted to the chemistry of this type of ligands.…”