Chemie freier, cyclischer vicinaler Tricarbonyl-Verbindungen (`1,2,3-Trione'), Teil 1, Reaktionsweise von Diazomethan und seinen Derivaten mit 5,5-Dimethylcyclohexan-1,2,3-trion (=`Oxo-dimedon') und verwandten Cyclohexan-1,2,3-trionen
摘要:
Interactions of diazomethane and of its derivatives as typical nucleophiles with cyclic 1,2,3-triones as efficient electrophiles lead to different results: a) formation of oxiranes (C,O insertion under loss of N-2), b) nucleophilic addition yielding diazoaldols, c) formation of ring-enlargement products (C,C insertion under loss of N-2), and d) formation of dioxoles via redox reactions (under loss of N-2). Our results and those of other groups allow us to recognize that the unexpected outcome of the reaction of oxodimedone and several related species is due to a closed-shell diazoaldol formation followed by an open-shell redox reaction leading to dioxoles.
Facile synthesis of 1,2,3-tricarbonyls from 1,3-dicarbonyls mediated by cerium(IV) ammonium nitrate
作者:Akhil Sivan、Ani Deepthi
DOI:10.1016/j.tetlet.2014.01.145
日期:2014.3
A mild and efficient protocol for the synthesis of vicinal tricarbonyl compounds from β-dicarbonyls in a single step using cerium(IV) ammoniumnitrate as a catalytic oxidant is described. Ease of execution, wide substrate scope and the suitability for the synthesis of commercially important compounds like ninhydrin, alloxan and oxoline make this reaction particularly noteworthy.
Oxidation of diazo compounds by triphenyl phosphite ozonide. Quenching of singlet oxygen by diazo compounds
作者:V. V. Shereshovets、N. M. Korotaeva、A. S. Vorob'ev、V. D. Komissarov、I. I. Furlei
DOI:10.1007/bf00697131
日期:1994.9
The reaction of triphenyl phosphite ozonide with various types of diazo compounds results in their oxidation, which is accomplished by singletoxygen (1O2) evolved during thermal decomposition of the ozonide. A decrease in the ionization potential of the substrate results in an increase in the overall rate constant of quenching of1O2. In the case of 9-diazofluorene, the main channel of1O2 quenching
Ozonolytic Fragmentation of Phenyliodonium β-Diketonates; A Convenient Synthesis of Unsolvated<i>vic</i>-Triketones
作者:Kurt Schank、Carlo Lick
DOI:10.1055/s-1983-30350
日期:——
Chemie freier cyclischer vicinaler Tricarbonyl-Verbindungen (‘1,2,3-Trione') Teil 2. Redox-Reaktionen von 1,2,3-Trionen mit En-1,2-diolen (‘Reduktonen'), 2-Alkoxy-en-1-olen, En-1,2-diaminen und verwandten Spezies Für Teil 1, s. [1].
Chemistry of Free Cyclic Vicinal Tricarbonyl Compounds (‘1,2,3-Triones'). Part 2. Redox Reactions of 1,2,3-Triones with Ene-1,2-diols (‘Reductones'), 2-Alkoxy-en-1-ols, Ene-1,2-diamines, and Related Species. Midstanding carbonyl groups of cyclic 1,2,3-triones 4 possess outstanding electrophilic (electron-pair accepting) as well as oxidizing (one-electron accepting) properties. Their reactions with