Cs2CO3 as a source of carbonyl and ethereal oxygen in a Cu-catalysed cascade synthesis of benzofuran [3,2-c] quinolin-6[5-H]ones

2016 ◽  
Vol 14 (25) ◽  
pp. 5940-5944 ◽  
Author(s):  
Wajid Ali ◽  
Anju Modi ◽  
Ahalya Behera ◽  
Prakash Ranjan Mohanta ◽  
Bhisma K. Patel
Keyword(s):  
Ethereal Oxygen

Simultaneous construction of C–C, C–O, and C–N bonds utilizing Cs2CO3 as a source of carbonyl (CO) and ethereal oxygen and a cascade synthesis of benzofuro[3,2-c]quinolin-6(5H)-one are achieved using a combination of Cu(OAc)2 and Ag2CO3.

scholarly journals Studies on the formation of complex oxidation and condensation products of phenols. Part III. -Rearrangements of oxidation-reduction type in the diquinone group

1933 ◽  
Vol 143 (848) ◽  
pp. 223-228 ◽  
Keyword(s):  
Hydroxyl Group ◽  
Hydrogen Atoms ◽  
Blue Colour ◽  
Highly Active ◽  
Oxidation Reduction ◽  
Intramolecular Reactions ◽  
Trimethyl Ether ◽  
Free Hydroxyl ◽  
Ethereal Oxygen ◽  
Complex Oxidation

The diquinones have been but little investigated, and as they contain two condensed highly active quinonid systems it is to be anticipated that they should be capable of interesting intramolecular reactions. When heated to 210-215º, 4 : 4'-dimethoxydiquinone is rapidly converted into a red crystalline isomeride (yield, 90%), soluble in alkali with an intense blue colour, and yielding a mono-acetate indicating the occurrence of a free hydroxyl group. Two hydrogen atoms are taken up on reduction, and the phenolic product yields a triacetate and a trimethyl ether. It follows that of the four carbonyl oxygens of 4 : 4'-dimethoxydiquinone, one has been converted into a hydroxyl group, and another which does not exhibit any functional activity, is probably present as ethereal oxygen. These results led to formula (III) as representing the product of rearrangement.

Analytical Methods in Rubber Chemistry, Part I. General Analytical Considerations

1941 ◽  
Vol 14 (3) ◽  
pp. 628-640 ◽  
Author(s):  
E. H. Farmer
Keyword(s):  
Average Chain Length ◽  
Complex Molecules ◽  
Analytical Technique ◽  
Or Groups ◽  
Hydrocarbon Chains ◽  
Infinite Degree ◽  
Degree Of Degradation ◽  
Ethereal Oxygen ◽  
Made In

Abstract One of the consequences of the high-molecular character of rubber is the smallness of the effect on ultimate quantitative analysis of the presence of one or even several heteroatoms or groups in the long hydrocarbon chains. With rubber molecules possessing an average chain-length of about 4,500 isoprene units, the association of, say, ten nitrogen atoms wtih each chain would provide a nitrogen content of only about 0.0007 per cent, and the incorporation of about 0.005 per cent of ethereal oxygen in pure rubber hydrocarbon would be theoretically capable of providing sufficient linking material for an infinite degree of hetero-polymerization, or, if the oxygen were applied instead to produce the maximum possible degree of degradation, it would be capable of severing from one-quarter to one-third of the rubber chains. In view of these dimensions, and the fact that natural rubber normally contains difficultly removable hetero components, and is ready to take up additional amounts of oxygen, little progress can be made in the fundamental investigation of the complex molecules without a suitably accurate technique of chemical analysis, and this applies particularly to the determination of total oxygen and total nitrogen, and also to the determination of the six types of combined oxygen likely to be present in rubber, viz., hydroxylic, oxido-, ethereal, peroxidic, carbonyl and carboxylic. Unfortunately, great precision in estimation cannot be achieved without increasing greatly the rigour of the analytical technique, and perhaps it is not surprising that Midgley, Henne and Renoll's well-known high-precision method for determining carbon, hydrogen and, by difference, oxygen, still remains after five years the sole such chemical analytical method reported in the literature.

STUDIES ON THE URANIUM EXTRACTION EQUILIBRIA, PHOTOLYTIC, AND HYDROLYTIC REACTIONS IN SYSTEMS CONTAINING TRI-n-BUTOXYETHYL PHOSPHATE

1964 ◽  
Vol 42 (4) ◽  
pp. 878-884 ◽  
Author(s):  
M. Halpern ◽  
T. Kim ◽  
A. S. Kertes ◽  
N. C. Li
Keyword(s):  
Aqueous Solution ◽  
Hydrochloric Acid ◽  
Organic Phase ◽  
Acid Content ◽  
Tributyl Phosphate ◽  
Extraction Behavior ◽  
Initial Aqueous Solution ◽  
Hydrolysis Of ◽  
Ethereal Oxygen ◽  
Extraction Equilibria

The extraction equilibria in the system aqueous hydrochloric acid – uranyl chloride –undiluted tri-n-butoxyethyl phosphate, TBEP, were examined as a function of increasing uranyl concentration (0.44 to 4.41 M) in the initial aqueous solution, the acid content of the initial aqueous solution being kept constant at 6.76 M. The extraction behavior of TBEP is found to be different from that of tributyl phosphate. Evidence has been presented to show that the three ethereal oxygen atoms in the TBEP molecule are, under high organic phase loading conditions, available for participation in complexation. The hydrochloric acid promoted hydrolysis of TBEP and the instability toward light of the TBEP layer containing hydrochloric acid and uranium were also examined.

Microwave-assisted Claisen Rearrangement of 1-Allyloxy-4-hydroxybenzene in the Presence of Metal Salt

2021 ◽  
Vol 07 ◽  
Author(s):  
Fumiyoshi Ozaki ◽  
Yutaka Okada
Keyword(s):  
Alkali Metal ◽  
Lewis Acid ◽  
Claisen Rearrangement ◽  
Metal Salt ◽  
Alkali Metal Salt ◽  
Metal Salts ◽  
Hydroxyl Group ◽  
Microwave Assisted ◽  
Ethereal Oxygen

: Microwave-assisted Claisen rearrangement of allyloxybenzene with a hydroxyl group was conducted in the presence of metal salts. The rearrangement was promoted in the presence of an alkali metal salt, because the reaction substrate was converted to a phenoxide-type ion, which can efficiently absorb microwaves. In contrast, a Lewis acid was strongly coordinated to the ethereal oxygen, and this structure could also absorb microwaves efficiently.

Synthesis of Macrocyclic Amides and Their Intermediate 2 : 1 and 3 : 2 Reaction Compounds from Diethyl Oxalate and Ethereal Oxygen-Containing Diamines

1996 ◽  
Vol 69 (5) ◽  
pp. 1397-1401 ◽  
Author(s):  
Naoaki Fukada ◽  
Tadashi Ohtsu ◽  
Masamichi Miwa ◽  
Masayuki Mashino ◽  
Yasuyuki Takeda
Keyword(s):  
Diethyl Oxalate ◽  
Ethereal Oxygen

scholarly journals Synthesis, crystal structure and properties of [Co(L)2](ClO4)2 (L=1,3-bis(1H-benzimidazol-2-yl)-2-oxapropane)

2015 ◽  
Vol 80 (1) ◽  
pp. 45-51 ◽  
Author(s):  
Aydin Tavman ◽  
Cigdem Sayil
Keyword(s):  
Thermogravimetric Analysis ◽  
Elemental Analysis ◽  
Analysis Data ◽  
Molar Conductivity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Coordination Bonding ◽  
Ft Ir ◽  
Uv Visible ◽  
Ethereal Oxygen

The reaction of 1,3-bis(1H-benzimidazol-2-yl)-2-oxapropane (L) with Co(ClO4)2?6H2O in absolute ethanol produces di[1,3-bis(1H-benzimidazol-2-yl)-2-oxapropane-k2N,N?]cobalt(II)diperchlorate chelate complex ([Co(L)2](ClO4)2, 1). The complex 1 was characterized by elemental analysis, magnetic moment, molar conductivity, thermogravimetric analysis, FT-IR, UV-visible, mass spectrometry, and its solid state structure was determined by single crystal X-ray diffraction. According to the thermogravimetric analysis data, there is no any water coordinated or uncoordinated in 1 as well as elemental analysis. The complex 1 has 1:2 M:L ionic characteristic according to the molar conductivity. In the complex, the distances between the cobalt and the ethereal oxygen atoms (Co1-O2: 2.805(3); Co2-O1: 2.752(2) ?) show the semi-coordination bonding and the Co(II) ion is six-coordinated with a N4O2 ligand set, resulting in a distorted octahedron.

Chemical Basis for High Activity in Oxygenation of Cyclohexane Catalyzed by Dinuclear Iron(III) Complexes with Ethereal Oxygen Containing Ligand and Hydrogen Peroxide System

1997 ◽  
Vol 52 (6) ◽  
pp. 719-727 ◽  
Author(s):  
Sayo Ito ◽  
Takashi Okuno ◽  
Hiroki Itoh ◽  
Shigeru Ohba ◽  
Hideaki Matsushima ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Oxygen Atom ◽  
Bond Cleavage ◽  
Structural Features ◽  
Active Species ◽  
Electronic Interaction ◽  
Ligand System ◽  
Dinuclear Iron ◽  
Binuclear Iron ◽  
Ethereal Oxygen

Abstract The crystal structures of two binuclear iron(III) complexes with linear μ-oxo bridge, Fe2OCl2 (tfpy)2 (ClO4)2 ·2CH3CN and Fe2OCl2(epy)2(ClO4)2 were determined, where (tfpy) and (epy) represent N,N-bis(2-pyridylmethyl)-tetrahydrofurfurylamine and N,N-bis(2-pyridylmethyl)-2-ethoxyethylamine, respectively. Their structural features are essentially the same as that of the corresponding linear binuclear complex with (tpa)-complex, Fe2OCl2(tpa)2(ClO4)2, where (tpa) is tris(2-pyridylmethyl)amine; the ligands (tfpy) and (epy) act as a tetradentate tripod-like ligand, and Fe-O (ethereal oxygen atom; these are located at the trans-position of bridging oxo-oxygen atom) distances are 2.209(4) and 2.264(2) Å for (tfpy) and (epy) compounds, respectively. These two (tfpy) and (epy) complexes exhibited much higher activity for the oxygenation of cyclohexane in the presence of hydrogen peroxide than that of the (tpa) complex. In contrast to this, the former two complexes exhibit negligible activity for the decomposition of hydrogen peroxide, whereas the catalase-like function of the (tpa) compound is remarkable. These are indicating that an active species for oxygenation of cyclohexane, which is assumed to be an iron(III)-hydroperoxide adduct with η1-coordina­tion mode, should be different from that is operating for decomposition of hydrogen perox­ide; for the latter case formation of a (μ-η1:η1-peroxo)diiron(III) species being stressed. The EHMO calculation showed that electronic interaction between the monodentate hydroperox­ide adduct of the binuclear iron(IIl)-(tfpy) compound and the tetrahydrofuran ring of the ligand system may lead to facile peroxide-tetrahydrofuran linkage formation, and the interac­tion described above should promote the O-O cleavage of the peroxide ion heterolytically. Based on these discussions, it was concluded that heterolytic O-O bond cleavage of the iron(III)-hydroperoxide adduct caused by electronic interaction with organic moiety contain­ing an ethereal-oxygen and by approach of the substrate which donates electron to the perox­ide adduct should play an important role in producing a high-valent iron-oxo species in these systems. In the case of (tpa) complex, formation of a hydroperoxide adduct linking with the ligand system seems to be unfavorable because of both the steric and electronic reasons.

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