156994-29-5Relevant articles and documents
Modeling the formation and reactions of benzene metabolites
Golding, Bernard T.,Barnes, Martine L.,Bleasdale, Christine,Henderson, Alistair P.,Jiang, Dong,Li, Xin,Mutlu, Esra,Petty, Hannah J.,Sadeghi, Majid M.
, p. 196 - 200 (2010)
One or more of the muconaldehyde isomers is a putative product of benzene metabolism. As muconaldehydes are highly reactive dienals and potentially mutagenic they might be relevant to the carcinogenicity of benzene. Muconaldehydes may be derived through the action of a cytochrome P450 mono-oxygenase on benzene oxide-oxepin, which are established metabolites of benzene. Oxidation of benzene oxide-oxepin either by the one-electron oxidant cerium(IV) ammonium nitrate (CAN) or by iron(III) tris(1,10-phenanthroline) hexafluorophosphate in acetone at -78°C or acetonitrile at -40°C gave (E,Z)-muconaldehyde, which was a single diastereoisomer according to analysis by 1H NMR spectroscopy. Reaction of toluene-1,2-oxide/2-methyloxepin with CAN gave (2E,4Z)-6-oxo-hepta-2,4-dienal. Similarly, the action of CAN on 1,6-dimethylbenzene oxide-2,7-dimethyloxepin gave (3Z,5E)-octa-3,5-diene-2,7-dione. In vivo, benzene oxide-oxepin could suffer one-electron oxidation by cytochrome P450 mono-oxygenase giving (E,Z)-muconaldehyde. The observations presented may be relevant to the toxicology of benzene oxide-oxepin and other arene oxide-oxepins as we have previously shown that (E,Z)-muconaldehyde, analogously to (Z,Z)-muconaldehyde, affords pyrrole adducts with the exocyclic amino groups of the DNA bases adenine and guanine. Independent of their possible toxicological significance, the experiments described provide preparatively useful routes to (E,Z)-muconaldehyde and its congeners. Methods are also described for the trapping and analysis of reactive benzene metabolites, e.g. using the Diels-Alder reaction with the dienophile 4-phenyl-1,2,4-triazoline-3,5-dione to trap arene oxides and with the diene 1,3-diphenylisobenzofuran to trap enals.
Ruthenium-catalyzed stereo- and chemoselective oxidative coupling of vinyl ketones: efficient access to (E,E)-1,6-dioxo-2,4-dienes
Beeralingappa, Nagabhushana C.,Bhat, Arsheed A.,Dethe, Dattatraya H.,Kumar, Vimlesh,Mishra, Kunj B.,Nirpal, Appasaheb K.,Srivastava, Aparna
supporting information, p. 3063 - 3066 (2022/03/15)
A Ru-catalyzed direct oxidative coupling reaction of vinyl ketones was developed. It offers a straightforward and atom-economical protocol for the synthesis of functionalized (E,E)-1,6-dioxo-2,4-diene derivatives in moderate to good yields with excellent stereo- and chemoselectivities. In addition, the synthetic utility of this method was further demonstrated by its application to the synthesis of bioactive natural products such as (7E,9E)-henicosa-7,9-diene-6,11-dione (sex pheromone), ostopanic acid (plant anticancer agent), JA (anti-tumor agent) and the southern part (C1-C13) of the antibiotic macrolactin-T.
N-Vinylpyridinium tetrafluoroborate salts as reagents for the stereoselective and regioselective synthesis of symmetrical (2E,4E)-1,6-dioxo-2,4-dienes
Gao, Ge,Brown, Neil,Minatoya, Machiko,Buszek, Keith R.
scheme or table, p. 6491 - 6494 (2009/04/06)
We had previously demonstrated the utility of N-vinylpyridinium tetrafluoroborate salts as novel electrophilic coupling partners in Pd(0)-catalyzed Suzuki cross-coupling reactions with aryl and vinyl boronic acids. We now report that these crystalline, air-stable, and non-hygroscopic salts are also useful reagents for the synthesis of symmetrical (2E,4E)-1,6-dioxo-2,4-dienes (diene diones), which in turn are valuable starting materials for the synthesis of various five-membered heterocycles. The optimization of reaction conditions and the scope and limitations of the reductive dimerization are discussed.
N-vinylpyridinium and -ammonium tetrafluoroborate salts: New electrophilic coupling partners for Pd(0)-catalyzed suzuki cross-coupling reactions
Buszek, Keith R.,Brown, Neil
, p. 707 - 710 (2007/10/03)
N-Vinylpyridinium and -trialkylammonium tetrafluoroborate salts represent a new class of electrophilic coupling partner for Pd(0)-catalyzed Suzuki cross-coupling reactions and give very good to excellent yields of products with a wide range of boronic acids. The salts are easily prepared from activated acetylenes and pyridinium or trialkylammonium tetrafluoroborates to form crystalline, air-stable, and nonhygroscopic crystals.
Convenient synthesis of 2,5-disubstituted thiophene from 1,6-dioxo-2,4- diene
Ong, Chi Wi,Chen, Chong Ming,Wang, Long Fu,Shieh, Po Chuen
, p. 9191 - 9192 (2007/10/03)
Reaction of 1,6-dioxo-2,4-diene with P2S5 and Lawesson's reagent affords the 2,5-disubstituted thiophene. This reaction can take place regioselectively in the presence of BF3-etherate catalysis, useful for the synthesis of
Thermal Rearrangements, XXII. The Propargyl-Cope Rearrangement of meso- and d,l-3,4-Dimethyl-1,5-hexadiyne-3,4-diol
Hopf, Henning,Hamann, Uwe,Zimmermann, Gerhard,Remmler, Matthias
, p. 959 - 964 (2007/10/02)
The thermal behavior of meso- and d,l-3,4-dimethyl-1,5-hexadiyne-3,4-diol (meso- and d,l-4) has been studied at 400 deg C in the gas phase.In a tandem reaction the diols isomerize via the bisallenes 5 first to cis- and trans-3,4-diacetylcyclobutene (cis- and trans-8) which have been detected as intermediates by 13C-NMR spectroscopy as well as catalytic hydrogenation to 1,2-diacetylcyclobutane (9).Subsequently, 8 stabilizes itself by ring opening to (E,Z)- and (E,E)-3,5-octadien-2,7-dione .As a side reaction retro-ene cleavage of 4 to 2-butynone (10) and methyl vinyl ketone (12) is observed.By pyrolysis of the pure diastereomers 4 it is shown that the retro-ene process is more pronounced in the d,l than in the meso series. - Key Words: Rearrangements, thermal / Propargyl-Cope reaction / 1,5-Hexadiyne-3,4-diol / Cyclobutene, 3,4-diacetyl- / Fragmentations, retro-ene / Tandem reactions
"Head-to-head" dimerization and dehydrodimerization of vinyl ketones catalyzed by modified rhodium(I) complexes
Kovalev, I. P.,Kolmogorov, Yu. N.,Strelenko, Yu. A.,Ignatenko, A. V.,Vinogradov, M. G.,Nikishin, G. I.
, p. 125 - 133 (2007/10/02)
The dimerization of vinyl ketones RC(O)CH=CH2, I (R = Me, tBu, Ph, p-MeC6H4, cyclopropyl, 2-(5-methylfuryl)) at 80 deg C in the presence of the catalytic system 2-MCl2 leads preferably to either α,β-unsaturated 1,6-diketones RC(O)C
