Zur Herstellung von 1,2,3‐Tricarbonylverbindungen aus 1,3‐Dicarbonylverbindungen. 27. Mitteilung über Reduktone und Tricarbonylverbindungen [1]

Abstract

The synthesis of 22 substituted tricarbonyl compounds is reported. They were obtained either by oxidation of β‐dicarbonyl compounds with SeO2 or nitrous oxides or by oxidation of the α‐bromo‐β‐dicarbonyl compounds with DMSO. The procedures using SeO2 or DMSO are more rapid and give in general better yields than other methods described in the literature.

Diaroyl(methanato)boron Difluoride Compounds as Medium‐Sensitive Two‐Photon Fluorescent Probes

“…[27] Lastly, MeOPheMeOPhe was directly obtained in one step from acylation of ethenyl acetate by 4-methoxybenzoyl chloride (pathway C). [28] Chemical stability against hydrolysis: During experiments performed in our laboratory, some BODIPY derivatives were prone to color fading in the presence of water. For example, during preparation of egg lecithin vesicles by detergent removal, the signal arising from a BODIPY-labeled Abstract in French: Cet article ÿvalue l×intÿrÜt de complexes difluoroboroniques de diaroyl-b-dicÿtones dans l×ÿlaboration de sondes fluorescentes aprõs excitation ‡ deux photons.…”

“…Reflux was continued for 5 min and water (5 mL) was added. Syntheses of the diketones Ar 1 Ar 2 along pathway C 1,3-Di(4-methoxyphenyl)propane-1,3-dione (MeOPheMeOPhe): [28] A suspension of 4-methoxybenzoyl chloride (1.67 g, 9.8 mmol) and aluminium chloride (1.4 g, 10.25 mmol) in tetrachloroethane (5 mL) was stirred at 55 8C for 2 h. Then, ethenyl acetate (430 mg, 5 mmol) was added and the mixture was further stirred at 55 8C for 20 h. After cooling to room temperature, hydrochloric acid (2 m, 2 mL) and water (20 mL) were successively added. After extraction with ethyl acetate, the organic phase was washed with sodium hydrogencarbonate and water.…”

GP96 C‐terminal improves Her2/neu DNA vaccine

“…This compound was subsequently brominated26 to yield 2 B‐BiPhe, which finally gave BiPhe after elimination under basic conditions 27. Lastly, MeOPheMeOPhe was directly obtained in one step from acylation of ethenyl acetate by 4‐methoxybenzoyl chloride (pathway C) 28…”

“…1,3‐Di(4‐methoxyphenyl)propane‐1,3‐dione (MeOPheMeOPhe) :28 A suspension of 4‐methoxybenzoyl chloride (1.67 g, 9.8 mmol) and aluminium chloride (1.4 g, 10.25 mmol) in tetrachloroethane (5 mL) was stirred at 55 °C for 2 h. Then, ethenyl acetate (430 mg, 5 mmol) was added and the mixture was further stirred at 55 °C for 20 h. After cooling to room temperature, hydrochloric acid (2 M , 2 mL) and water (20 mL) were successively added. After extraction with ethyl acetate, the organic phase was washed with sodium hydrogencarbonate and water.…”

Synthesis of α,β‐Dicarbonylhydrazones by Aerobic Manganese‐Catalysed Oxidation

“…On the other hand, the oxidation of a methylene group α to a carbonyl group to form vicinal dicarbonyl compounds is an important transformation which has many applications in organic synthesis as building blocks for the synthesis of bioactive molecules, especially those containing heterocycles . Conventional reagents for accomplishing this transformation, including strong oxidants such as selenium oxide, 2‐iodoxybenzoic acid (IBX), Dess‐Martin reagent or cerium(IV) salts, often lead to further oxidation or side reactions because of the strong reaction conditions employed. Additionally, these processes usually require stoichiometric or large excess of oxidants and, consequently, generate substantial quantities of waste, which is increasingly considered undesirable due to environmental considerations.…”