6333-11-5Relevant academic research and scientific papers
Preparation method of α,β- or β,β-dihaloenones from diazodicarbonyls
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Paragraph 0031; 0038-0039; 0125-0126, (2017/08/30)
The present invention relates to a method for preparing andalpha;,andbeta;- or andbeta;,andbeta;-dihaloenone compounds from diazodicarbonyl compounds. According to the present invention, a diazo compound reacts with an oxalyl halide in the presence of a ruthenium catalyst so andalpha;,andbeta;- and andbeta;,andbeta;-dihaloenones can be synthesized through one-step reaction in an easy, simple and environmental manner. The synthesized andalpha;,andbeta;- and andbeta;,andbeta;-dihaloenones can be widely used for synthesis of intermediates of various drugs, natural materials, agricultural pesticides, dyes, etc. due to various biological activities.COPYRIGHT KIPO 2017
Ruthenium(II)-catalyzed protocol for preparation of diverse α,β- and β,β-Dihaloenones from diazodicarbonyls
Magar, Krishna Bahadur Somai,Lee, Yong Rok
, p. 3422 - 3432 (2015/02/02)
Efficient one-step syntheses of α,β- and β,β-dihaloenones were achieved by ruthenium(II)- catalyzed reactions between cyclic or acyclic diazodicarbonyl compounds and oxalyl chloride or oxalyl bromide in moderate to good yields. This methodology offers sev
Sequential multiple-photon photochemistry of sterically congested enones
Schnapp, Karlyn A.,Motz, Philip L.,Stoeckel, Sharon M.,Wilson, R. Marshall,Krause Bauer, Jeanette A.,Bohne, Cornelia
, p. 2317 - 2320 (2007/10/03)
The photochemistry of sterically hindered enones 1 and 2 is described. A novel photorearrangement occurs in both systems which involves carbonyl attack on the adjacent phenyl ring, expansion of that ring to a cycloheptatriene and subsequent photochemically induced 1,7-phenyl migration.
Hypervalent iodine oxidation of allenes: Synthesis of 3-acetoxy-3-alkoxypropynes, 2-alkoxy-3-tosyloxypropanals and phenyl-substituted propenals and propenones
Moriarty,Hopkins,Vaid,Vaid,Levy
, p. 847 - 849 (2007/10/02)
1-Alkoxyallenes yield 3-acetoxy-3-alkoxypropynes upon oxidation with [(diacetoxy)iodo]benzene at -78°C in dichloromethane. Treatment with [hydroxy(tosyloxy)iodo]benzene under similar conditions gives 2-alkoxy-3-tosyloxypropanals. Phenyl-substituted propen
Electron Transfer Reactions. Reaction of Furanones and Bifurandiones with Potassium and Oxygen
Pandey, Bipin,Tikare, Ravindra K.,Muneer, Mohammed,Kamat, Prashant V.,George, Manapurathu V.
, p. 917 - 928 (2007/10/02)
Treatment of furanones (1a - c, 25, 34) and bifurandiones (23, 37) with potassium in THF gave rise to radical anion intermediates, which reacted with oxygen to give superoxide and ultimately products derived through the reaction of superoxide with the starting furanones and bifurandiones.Thus, the reaction of 1a with potassium gave a mixture of 4-oxo-2,2,4-triphenylbutanoic acid (7a), 1,3,3-triphenyl-2-propen-1-one (11a), and benzoic acid (12).The reaction of 11a itself, under similar conditions, gave a mixture of benzophenone (18a) and 12.Similar reactions have been observed in the case of 1b and c.The bifurandione 23, on treatment with potassium, gave a mixture of the 2(5H)-furanone 25, 2,3-diphenylpropenoic acid (31), and 12.The reaction of 25 itself with potassium under similar conditions gave the same mixture of 31 and 12.Treatment of 3-phenyl-2(3H)-benzofuranone (34) with potassium, however, did not give any isolable product; only the starting material could be recovered.Under similar conditions, the bifurandione 37 gave the fragmentation product 34.Cyclic voltammetric studies have been employed to measure the reduction potentials, leading to radical anions, and these intermediates have been characterized through their electronic spectra.
Photochemical and Thermal Transformations of 2(3H)-Furanones and Bis(benzofuranones). A Laser Flash Photolysis study
Lohray, B. B.,Kumar, C. V.,Das, P. K.,George, M. V.
, p. 7352 - 7359 (2007/10/02)
Transformations of the 2(3H)-furanones 1-4 and bis(benzofuranones) 16-18 under steady-state photolysis and thermolysis are reported.Irradiation of 1 in benzene gives a mixture of the decarbonylated product 5 (62percent) and the cyclized phenanthrene derivative 10 (15percent).Similar results were obtained when the photolysis of 1 was carried out in methanol and acetone.Irradiation of 2 in benzene and methanol gave exclusively the decarbonylation product 6, whereas, in acetone, a mixture of the rearranged lactone 13 and and its cyclized product, 15, was obtained.Irradiation of both 3 and 4 gave the cyclized products 11 and 12, respectively.In contrast, the photolysis of the bis(benzofuranone) 16 in cyclohexane gave 3-phenylbenzo-2-(3H)-furanone (25), whereas the photolysis in methanol led to a mixture of methyl α-(2-hydroxyphenyl)phenylacetate (34) and 3-hydroxy-3-phenylbenzo-2(3H)-furanone (31).Similar results were obtained in the irradiation of 17 and 18.Neat thermolysis of furanones 1-3 at 350-450 deg C gave the decarbonylated products 5, 6, and 37 in 36-80 percent yields, whereas furanone 4 underwent facile isomerization to 5-benzyl-3,4,5-triphenyl-2(5H)-furanone (38), upon refluxing in diphenyl ether (ca. 255 deg C).Heating of bis(benzofuranones) 16-18 in refluxing cumene (ca. 150 deg C) gave the corresponding furanones 25-27 in 62-68 percent yields.Laser flash photolysis of furanones 1-4 at 248 and 337 nm leads to absorption spectral changes that can be explained in terms of singlet-mediated decarbonylation (φ = 0.3 for 2 in methanol, λex = 248 nm) and cyclization, i.e., dihydrophenanthrene formation (φ = 0.1-0.5 for 1, 3, and 4 in benzene and methanol, λex = 337 nm).The triplets of the furanones generated under energy-transfer sensitization by benzophenone in benzene are relatively long lived (r = 1.2-12 μs) and exhibit absorption maxima at 330-370 nm (εmax = (11-14) * 103 M-1 cm-1); these spectral and kinetic features appear to be characteristic of the styrene and cis-stilbene chromophores, constrained into planar configurations.Upon laser flash photolysis at 248 nm in methanol, bis(benzofuranones) 16-18 undergo facile fragmentation to the corresponding radicals 19-21, characterized by sharp and intense absorption maxima at ca. 330 nm, in addition to broad and weak absorption band systems at 500-600 nm; these radical species are the primary intermediates implicated in the formation of various final products in the course of steady-state photolysis of 16-18 under different conditions.
Effects of strong π-electron accepting substituents on structure preference for thiocarbonyl ylide or thiirane
Oka, Kitaro,Dobashi, Akira,Hara, Shoji
, p. 3579 - 3582 (2007/10/02)
Equilibrium between thiocarbonyl ylide and thiirane depends upon the π-electron accepting nature of the substituents. Four carbonyl and ester groups move the equilibrium far to the thiocarbonyl ylide side.
