Browsing by Subject "chemical reaction"
Now showing items 21-39 of 39
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A qualitative comparison of the reactivities of 3,4,4,5-Tetrachloro-4H-1,2,6-thiadiazine and 4,5-Dichloro-1,2,3-dithiazolium Chloride
(2015)The high yielding transformations of 3,4,4,5-tetrachloro-4H-1,2,6-thiadiazine into 3,5-dichloro-4H-1,2,6-thiadiazin-4-one (up to 85%) and 2-(3,5-dichloro-4H-1,2,6- thiadiazin-4-ylidene)malononitrile (up to 83%) have been ...
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Reaction of tetracyanoethylene with SCL2: New molecular rearrangements
(2000)The chloride ion catalysed addition of SCl2 to TCNE gives the dicyanomethylene-1,2,6-thiadiazine 3 as major product together with two unexpected minor products, pyrimidine 4 and pyrroloimidazothiadiazine 5, whose X-ray ...
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Reactions of tetracyanoethylene with N′-arylbenzamidines: A route to 2-phenyl-3 H -imidazo[4,5- b ]quinoline-9-carbonitriles
(2013)Eight 2-phenyl-3H-imidazo[4,5-b]quinoline-9-carbonitriles 15 are prepared in four steps from N′-arylbenzamidines 11 and tetracyanoethylene (TCNE) in ∼70-90% yields. The transformation involves the initial formation of ...
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Article
Regioselective hydrodehalogenation of 3,5-dihaloisothiazole-4- carbonitriles: Synthesis of 3-haloisothiazole-4-carbonitriles
(2011)3,5-Dibromoisothiazole-4-carbonitrile 1 treated with Zn or In dust (5 equiv) and HCO2H undergoes regioselective hydrodebromination to give 3-bromoisothiazole-4-carbonitrile 3 in 70-74% yield. Similarly, 5-bromo and iodo ...
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Reinvestigating the reaction of 1H-pyrazol-5-amines with 4,5-dichloro-1,2,3-dithiazolium chloride: A route to pyrazolo[3,4-c]isothiazoles and pyrazolo[3,4-d]thiazoles
(2014)The reaction of Appel salt 1 with 1H-pyrazol-5-amines 2 gives main products N-(4-chloro-5H-1,2,3-dithiazol-5-ylidene)-1H-pyrazol-5-amines 3, and 6H-pyrazolo[3,4-c]isothiazole-3-carbonitriles 5, together with several minor ...
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The remarkable effect of oxygen on the N2 selectivity of water catalytic denitrification by hydrogen
(2007)The selective catalytic reduction of nitrates (NO3-) in pure water toward N2 formation by the use of gaseous H2 and in the presence of O2 (air) at 1 atm total pressure and 25°C has been investigated over Pd-Cu supported ...
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Ring opening of the cyclopropylcarbinyl radical and its N- and O- substituted analogues: A theoretical examination of very fast unimolecular reactions
(1998)High level ab initio molecular orbital calculations have been used to examine the ring opening of the cyclopropylcarbinyl radical and its heterosubstituted analogues. The applicability of various theoretical techniques to ...
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Stereochemistry of the [4 + 2] cycloadditions of trans,trans- and cis,trans-2,4-hexadiene to C60
(2002)The [4 + 2] cycloaddition of trans,trans-2,4-hexadiene with C60 proceeds via a concerted mechanism with retention of stereochemistry in the cycloadduct 1a. However, when cis,trans-2,4-hexadiene reacts with C60, isomerization ...
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Substitution at C-4 in 3,5-disubstituted 4H-1,2,6-thiadiazin-4-ones
(2012)3,5-Diaryl-4H-1,2,6-thiadiazin-4-ones react with NaBH 4 to give the 3,5-diaryl-4H-1,2,6-thiadiazin-4-ols and with MeLi to give 4-methyl-3,5-diaryl-4H-1,2,6-thiadiazin-4-ols. The latter dehydrate with p-toluenesulfonic acid ...
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Synthesis and aqueous solution properties of multinuclear oxo-bridged vanadium(IV/V) complexes
(2000)Reaction of the multifunctional phenolic ligands 2,5-bis[N,N-bis(carboxymethyl)aminomethyl]hydroquinone (H6cahq), 2,2'-bis[N,N-bis(carboxymethyl)aminomethyl]-4,4'-isopropylidenedi phenol (H6capd), 2,2',2''-tris[N,N-bis(c ...
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Synthesis of a novel diene from a cyclobutane precursor: An entry to 2,9-disubstituted [2]diadamantanes
(2013)In the gas-phase thermolysis (350 C) of heptacyclic cyclobutane 2, n=1, (the [2+2] dimer of noradamantene) two isomeric dienes (the symmetric 5, n=1 and the asymmetric 6a) and the reduction product [2]diadamantane (7-H) ...
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Synthesis of fused 1,2,4-dithiazines and 1,2,3,5-trithiazepines
(2014)Reacting ( Z)-N-(4-chloro-5H-1,2,3-dithiazol-5-ylidene)-1H-pyrazol-5-amines 5 with Et2NH and then with concd H2SO4 gives 5H-pyrazolo[3,4-e ][1,2,4]dithiazine-3-carbonitriles 7 in good yields (74-85%) and 6H-pyrazolo-[3,4 ...
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Synthesis of sulfur containing analogues of the soluble guanylate cyclase inhibitor 8-bromo-4H-[1,2,4]oxadiazolo[3,4-c][1,4]benzoxazin-1-one NS2028
(2011)Sulfur analogues of the soluble guanylate cyclase (sGC) inhibitor NS2028 1a are synthesized. Treating 8-bromo-2H-benzo[b][1,4]oxazin-3(4H)-one oxime (6) with 1,1′-thiocarbonyldiimidazole (1.1 equiv) gave the carbamothioate ...
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Synthesis, structure, and solution dynamics of UO2 2+-hydroxy ketone compounds [UO2(ma)2(H 2O)] and [UO2(dpp)(Hdpp)2(H2O)] ClO4 [ma = 3-hydroxy-2-methyl-4-pyrone, Hdpp = 3-hydroxy-1,2- dimethyl-4(1H)-pyridone]
(2004)293(2) K) are as follows: (1) monoclinic space group C2/c, a = 14.561(7) Å, b = 14.871(9) Å, c = 7.250(4) Å, β = 95.40(4)°, Z = 4
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Synthetic analogs for oxovanadium(IV/V)-glutathione interaction: An NMR, EPR, synthetic and structural study of oxovanadium(IV/V) compounds with sulfhydryl-containing pseudopeptides and dipeptides
(2000)The reaction of [VO(CH3COO)2(phen)] (phen = 1,10-phenanthroline) with the sulfhydryl-containing pseudopeptides (scp), N-(2-mercaptopropionyl)glycine (H3mpg), N-(2-mercaptopropionyl)cysteine (H4m2pc), N-(3-mercaptopropion ...
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Synthetic libraries of tyrosine-derived bacterial metabolites
(2008)The preparation of a collection of 131 small molecules, reminiscent of families of long chain N-acyl tyrosines, enamides and enol esters that have been isolated from heterologous expression of environmental DNA (eDNA) in ...
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Template Synthesis and Single-Molecule Magnetism Properties of a Complex with Spin S = 16 and a [Mn8O8]8+ Saddle-Like Core
(2003)The compound [CeIVMn8IIIO8(O2CMe)12(H2O)4]·4H2O (1·4H2O) has been obtained from a template synthesis involving the reaction of the chain polymer {[MnIII(OH)(O2CMe)2]·(MeCO2H)·(H2O)}n (3) with Ce(IV). Compound 1 contains a ...
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Three-step synthesis of ethyl canthinone-3-carboxylates from ethyl 4-bromo-6-methoxy-1,5-naphthyridine-3-carboxylate via a Pd-catalyzed Suzuki-Miyaura coupling and a Cu-catalyzed amidation reaction
(2011)Ethyl canthin-6-one-1-carboxylate (1b) and nine analogues 1c-k were prepared from readily prepared ethyl 4-bromo-6-methoxy-1,5-naphthyridine-3- carboxylate (2b) via a three-step non-classical approach that focused on ...
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U(VI) mono-hydroxo humate complexation
(2007)The complexation of the uranyl ion with humic acid is investigated. The humic acid ligand concentration is described as the concentration of reactive humic acid molecules based on the number of humic acid molecules, taking ...