Showing papers by "Alan R. Katritzky published in 1986"
TL;DR: Amination a l'aide de l'amino-4 triazole-1,2,4, en presence de t-butanolate de K dans le DMSO as discussed by the authors.
Abstract: Amination a l'aide de l'amino-4 triazole-1,2,4, en presence de t-butanolate de K dans le DMSO
69 citations
66 citations
52 citations
TL;DR: The mechanism of the reactions of ammonia and benzaldehyde with three different beta-dicarbonyl compounds to form the corresponding dihyropyridines has been followed by NMR as discussed by the authors.
50 citations
TL;DR: In this paper, the authors examined the effects of macroscopic solvation using the self-consistent reaction field technique and concluded that the introduction of a dielectric media seems to have little effect on calculated geometries.
Abstract: We examine the effects of macroscopic solvation using the self-consistent reaction field technique. On the basis of ab initio, INDOSCF, and INDO/CI calculations we conclude that the introduction of a dielectric media seems to have little effect on calculated geometries. However, the charge distribution is effected: the presence of dielectric media allows greater local charge to develop. The dissociation of hydrogen fluoride is examined. With electron correlation, HF dissociates homolytically in the “gas” phase, but heterolytically in a “solvent” of dielectric constant of 80.
47 citations
TL;DR: Les reactions des acetyl- et benzoylacetates et des α-acetyl- and α-benzoylpropionates avec l'hydroxylamine a pH 10-12 conduisent a des melanges d'isoxazoline-2ones-5 and d'Isoxazolols-3 as discussed by the authors.
Abstract: Les reactions des acetyl- et benzoylacetates et des α-acetyl- et α-benzoylpropionates avec l'hydroxylamine a pH 10-12 conduisent a des melanges d'isoxazoline-2ones-5 et d'isoxazolols-3
41 citations
TL;DR: Preparation d'alkylthio-2' and arylthio -2' ethyl-4 pyridines and des sulfoxydes et sulfones correspondants as mentioned in this paper.
Abstract: Preparation d'alkylthio-2' et arylthio-2' ethyl-4 pyridines et des sulfoxydes et sulfones correspondants. Par quaternarisation suivie d'un traitement avec une base, il y a elimination du groupe protecteur et formation de thiols, acides sulfeniques, acides sulfiniques et sulfenamides
32 citations
TL;DR: In this paper, the detailed mechanistic pathways for the reactions of acetylacetone, methyl acetoacetate, and dimethyl malonate with a variety of amidines and ureas were elucidated.
Abstract: The detailed mechanistic pathways are elucidated for the reactions of acetylacetone, methyl acetoacetate, and dimethyl malonate with a variety of amidines and ureas. In many cases the identificatio...
31 citations
TL;DR: Tetrahydroisoquinoline was converted into several 1-substituted derivatives by using carbon dioxide both for N-protection and to give an intermediate carbanion stabilizing group as discussed by the authors.
30 citations
TL;DR: In this article, a range of ortho-substituted derivatives, using carbon dioxide both for M-protection and as an intermediate carbanion stabilizing group, and t -butyllithium to lithiate the ortho carbon atom, were derived.
28 citations
TL;DR: In this paper, the reaction of primary amines with acetonylacetone is shown by H-1, C-13 and N-15 NMR spectroscopy to proceed to the N-substituted -2, 5-dimethylpyrroles via the intermediacy of N -substitized imines.
TL;DR: Derivatives of four series of compounds derived from isomers of indoxyl with the nitrogen at the bridgehead and two further series of aza-analogues are prepared and their absorption properties studied as discussed by the authors.
TL;DR: In this paper, a range of 4-substituted 2-pyridones was prepared using one-pot protection method and their orientation of substitution was proved by X-ray analysis.
TL;DR: The reaction of bisazlactones (2-oxazolin-5-ones) with primary diamines containing additional secondary or tertiary amine functionality (e.g., diethylenetriamine, triethylenetetramine, or N-methyliminobispropylamine) readily produces polyamides which serve as precursors to a new class of heterocyclic polymers as mentioned in this paper.
Abstract: The reaction of bisazlactones (2-oxazolin-5-ones) with primary diamines containing additional secondary or tertiary amine functionality (e.g., diethylenetriamine, triethylenetetramine, or N-methyliminobispropylamine) readily produces polyamides which serve as precursors to a new class of heterocyclic polymers. Thermal cyclodehydration takes place under relatively mild conditions (180–200°C) to produce water-soluble polymers containing the 2-imidazolin-5-one heterocycle. Model reactions have been studied to verify this mode of cyclization and confirm the proposed polymer structure.
TL;DR: In this paper, the effects of the variation of solvent, pyridinium leaving group, N -substituent, and nitronate nucleophile have been studied in the C -alkylation of Nitronate anions.
TL;DR: La nitration, la sulfonation, and la bromation du compose du titre se produisent en position meta du groupe phenyl-1 as discussed by the authors, in which
Abstract: La nitration, la sulfonation et la bromation du compose du titre se produisent en position meta du groupe phenyl-1
TL;DR: In this paper, complete 13C NMR chemical shift assignments are reported for 32 1H-pyrrole-2-carboxylic acid esters and amides, bearing alkyl, phenyl, acetyl, alkoxycarbonyl and diethylamino substituents.
Abstract: Complete 13C NMR chemical shift assignments are reported for 32 1H-pyrrole-2-carboxylic acid esters and amides, bearing in addition alkyl, phenyl, acetyl, alkoxycarbonyl and diethylamino substituents. The substituent chemical shift effect for the 2-Ph group on the pyrrole ring carbon atoms is also reported.
TL;DR: The preparation of pyrylium salts containing ethoxycarbonyl, anthracenyl, and adamantyl substituents was described in this article, where the preparation was described of some novel pyryls.
TL;DR: In this paper, it was shown that at the borderline between first-order reaction via nucleophilic trapping of intimate ion-molecule pairs and firstorder reaction through the formation of free carbocations, both mechanisms proceed independently, without merging.
Abstract: Evidence is presented to demonstrate that at the borderline between first-order reaction via nucleophilic trapping of intimate ion–molecule pairs and first-order reaction via the formation of free carbocations, both mechanisms proceed independently, without merging. Similarly at the borderline between first-order (rate-determining formation) and second-order (rate-determining nucleophilic attack) reactions of intimate ion–molecule pairs, both reactions again proceed independently.
TL;DR: In this paper, it was shown that mono-, tri-, and penta-cyclic N-benzylpyridinium tetrafluoroborates undergo thermolysis in chlorobenzene as solvent to give products of benzylation both of the solvent and of the pyridine leaving group.
Abstract: Mono-, tri-, and penta-cyclic N-benzylpyridinium tetrafluoroborates undergo thermolysis in chlorobenzene as solvent to give products of benzylation both of the solvent and of the pyridine leaving group. Thermolysis alone, and in nitrobenzene as solvent, yielded mainly products of benzylation of the leaving group. The results support the previously postulated mechanism of unimolecular solvolysis of compounds of these types in non-polar solvents.
TL;DR: In this paper, the preparation and arrangement of manuscripts of reviews of heterocyclic chemistry is discussed, and the figures, tables, equations, chemical formulae, and abbreviations used in the literature are presented.
Abstract: Publisher Summary This chapter focuses on the preparation and arrangement of manuscripts of reviews of heterocyclic chemistry. The figures, tables, equations, chemical formulae, and abbreviations used in heterocyclic chemistry are also presented in the chapter. Manuscripts should be divided into sections and, where desirable, into subsections, each having a short descriptive title. Reviews of heterocyclic chemistry often deal with a particular group of compounds based on a single ring or group of closely related ring systems. A section on structure in reviews of heterocyclic chemistry covers several main divisions including theoretical methods, molecular dimensions, molecular spectra, thermodynamic aspects, and tautomerism. The tables present in the manuscripts of reviews of heterocyclic chemistry should be numbered, using roman numerals, in order of their mention in the text and is given a brief title. The reaction equations should be numbered, if reference is made to them in the text, by Arabic numbers enclosed in parentheses. When used in conjunction with numerals, abbreviations should be used for internationally accepted units. The suggested forms for abbreviations are— %, cm, cm 3 , gm, mg, kg, ml, °C, cal, and kcal.
TL;DR: In this paper, N-Aryl-mono-, -tri-tri-andpentacyclic pyridinium cations react with S- and C-nucleophiles to give: (i) simple addition of hydride at the α-ring position, (ii) nucleophilic addition of thiophenoxide at the γ-position, (iii) deprotonation at the 6position of a 5,6-dihydroquinolinium ring followed by prototropic shift to give a 1,2
TL;DR: Synthetic methods for 6-alkyl-, 6-aryl, and 6-heteroaryl-2,4-dichloro-1,3,5-triazines are described in this paper.
Journal Article•
01 Jan 1986
TL;DR: In this paper, a non-chain radical mechanism for the reactions of N-alkylpyridinium cations with nitronate anions was presented, where the first step is considered to be charge transfer.
Abstract: Evidence is presented for a non-chain radical mechanism for the reactions of N-alkylpyridinium cations with nitronate anions. The first step is considered to be charge-transfer. The extension of this type of reaction to other C-nucleophiles and to N-arylpyridinium cations is discussed.
TL;DR: Carbazoles react with a variety of one-carbon fragments at the 3- or 3,6-positions to give di- and trimeric products with CH2: links as discussed by the authors.
Abstract: Carbazoles react with a variety of one-carbon fragments at the 3- or 3,6-positions to give di- and trimeric products with CH2: links. These precursors react by losing hydride ion to give blue oligomeric dyes. Carbazoles substituted in the 9-position by CH2SPh, CH2SOPh, and CH2SO2Ph rearrange to give carbazole oligomers linked at the 3,6-positions. Products are characterised spectrally, and their mechanism of formation is discussed.