Showing papers by "Alan R. Katritzky published in 2000"
430 citations
247 citations
TL;DR: A successful interpretation of the complex manner by which the GC retention indexes of methylalkanes produced by insects are related to chemical structure was achieved using the quantitative structure-property relationship (QSPR) method.
Abstract: A successful interpretation of the complex manner by which the GC retention indexes of methylalkanes produced by insects are related to chemical structure was achieved using the quantitative structure−property relationship (QSPR) method. A general QSPR model including mainly topological descriptors was obtained for 178 data points. The error of the model is similar to the experimental error. The model was supported by (i) leave-one-out cross validation and (ii) division into three sets and prediction of each set from the other two. As a further test of the utility of the model, retention indexes were successfully predicted for an external set of 30 methyl-branched hydrocarbons not involved in the deduction of the correction equation from the main data set. General trends of the structural variation of compounds in any given range of retention index are discussed. The average error was 4.6 overall and 4.3 for the 165 compounds remaining after leaving out small monomethyl alkanes.
98 citations
TL;DR: In this article, the reactivity of organic molecules in pure superheated water is investigated from studies aimed at explaining how organic matter (kerogen) forms and then breaks down, in low temperature (
81 citations
TL;DR: In this paper, the liquid viscosity of 361 organic compounds containing C, H, N, O, S and/or halogens was investigated using a quantitative structure-property relationship (QSPR) approach.
63 citations
42 citations
40 citations
TL;DR: 2-Aminopyridines 1a-c and 1-aminoisoquinoline with 1-chloromethylbenzotriazole give 2-amino-1-[alpha-benzol-1-ylmethyl]pyridinium chlorides + chloride 12, respectively, which enable imidazolo[2, 1-a]isoquinolines 13a,b in good yields.
Abstract: 2-Aminopyridines 1a-c and 1-aminoisoquinoline with 1-chloromethylbenzotriazole give 2-amino-1-[alpha-benzotriazol-1-ylmethyl]pyridinium chlorides 2a-c and 1-amino-2-(alpha-benzotriazol-1-ylmethyl)isoquinolinium++ + chloride 12, respectively. Compounds 2a-c and 12 react with aryl aldehydes 3a-h to afford imidazolo[1,2-a]pyridines 7a-k and imidazolo[2, 1-a]isoquinolines 13a,b in good yields.
38 citations
TL;DR: 1-Phenyl-5-(benzotriazol-1-yl)hexahydro-1H-pyrrolo[1,2-a]ĭmidazoles and 1-phenyl- 5-substituted-octahydROimidazo[ 1, 2-a], while the configurations and conformations of 28a-e, 32, 33a,b, and 34 were elucidated.
Abstract: 1-Phenyl-5-(benzotriazol-1-yl)hexahydro-1H-pyrrolo[1,2-a]ĭmidazole (18) and 1-phenyl-5-benzotriazolyloctahydroimidazo[1,2-a]pyridine (27) were readily prepared from succindialdehyde or glutaraldehyde, benzotriazole, and N-phenylethylenediamine. Synthons 18 and 27 reacted with Grignard reagents, allylsilanes, silyl ethers, and triethyl phosphite to produce 1-phenyl-5-substituted-hexahydro-1H-pyrrolo[1,2-a]ĭmidazoles 20a-f, 22, 24a,b, and 25 and 1-phenyl-5-substituted-octahydroimidazo[1, 2-a]pyridines 28a-e, 32, 33a,b, and 34 in good to excellent yields. The configurations of 20, 22, 24, and 25 were determined to be cis isomers by NOE experiment, while the configurations and conformations of 28a-e, 32, 33a,b, and 34 were elucidated by (1)H-(1)H COSY and (1)H-(13)C COSY.
37 citations
TL;DR: Several substituted 2- and 4-hydroxyacetophenones are linked to Wang resin via a modified Mitsunobu protocol, and the resulting chalcones 5 are used for the synthesis of 2-dialkylaminos and 2-alkylamino-4,6-diarylpyridines in a manner suitable for combinatorial applications.
Abstract: Several substituted 2- and 4-hydroxyacetophenones are linked to Wang resin via a modified Mitsunobu protocol These resin-bound acetophenones are condensed with aromatic aldehydes, and the resulting chalcones 5 are used for the synthesis of 2-dialkylamino- (9a−d) and 2-alkylamino-4,6-diarylpyridines (11a−f), and 2-alkyl-4,6-diaryl- (14a) and 2,4,6-triarylpyrimidines (14b,c) in a manner suitable for combinatorial applications
30 citations
TL;DR: Numerous 1,2-diaryl(heteroaryl)pyrroles and -3-methylpyr roles were prepared in a two-step procedure from N-allylbenzotriazoles via intramolecular oxidative cyclization in the presence of Pd(II) catalyst.
Abstract: Numerous 1,2-diaryl(heteroaryl)pyrroles and -3-methylpyrroles were prepared in a two-step procedure from N-allylbenzotriazoles via intramolecular oxidative cyclization in the presence of Pd(II) catalyst.
TL;DR: One-carbon homologation of carboxylic acids is achieved by treatment of an acyl chloride with 1-[(trimethylsilyl)methyl]-1H-1,2, 3-benzotriazole to afford esters RCH( 2)CO(2)R' 7a-c in overall yields of 50-70%.
TL;DR: The thiazolo[3,2-b]1,2,4-triazoles 5a-f, which resemble closely some previously prepared COX-2 inhibitors, are confirmed by X-ray analysis.
TL;DR: Lewis acid-catalyzed alpha-amidoalkylation of enolizable aldehydes with N-(alpha-benzotriazolyl-alpha-arylalkyl)amides followed by intramolecular Friedel-Crafts cyclization provides a convenient route to 2-substituted 1-aminoindenes.
Abstract: Lewis acid-catalyzed α-amidoalkylation of enolizable aldehydes with N-(α-benzotriazolyl-α-arylalkyl)amides followed by intramolecular Friedel−Crafts cyclization provides a convenient route to 2-substituted 1-amidoindenes.
TL;DR: In this paper, direct O-alkylation of 2-hydroxy-5-methoxybenzaldehyde (1) with alkyl bromides or iodides gave nine 2-alkoxy-5 methoxy-benzaldehydes 2a-i in high yields, six of which were novel compounds.
Abstract: Direct O-alkylation of 2-hydroxy-5-methoxybenzaldehyde (1) with alkyl bromides or iodides gave nine 2-alkoxy-5-methoxybenzaldehydes 2a-i in high yields, six of which are novel compounds. Treatment of 2-ethoxy-5-bromobenzaldehydes (3) with n-BuLi, morpholine and nitrobenzene afforded 2-ethoxy-5-hydroxybenzaldehyde (4), which easily underwent Oalkylation to furnish 2-ethoxy-5-alkoxybenzaldehydes 5a-b in total moderate yields.
TL;DR: In this paper, the formylation with DMF of α- lithio benzofuran, benzothiophene, N-methylbenzimidazole and 10-methylphenothiazine obtained by direct lithiation and β-lithio compounds from lithium-bromine exchange.
Abstract: Heteroaromatic α- and β-carboxaldehydes were prepared by the formylation with DMF of α- lithio benzofuran, benzothiophene, N-methylbenzimidazole and 10-methylphenothiazine obtained by direct lithiation and β-lithio compounds from lithium-bromine exchange. Dialkoxybenzaldehydes were prepared by the formylation of dialkoxybenzenes with hexamethylenetetramine (HMTA) or by the alkylation of dihydroxybenzaldehydes with alkyl bromides or iodides.
TL;DR: Katritzky et al. as discussed by the authors proposed Bis-4-halophenyl-pyrimidines and -1,2,4,5-tetrazines.
Abstract: ISSN 1424-6376 Page 37 ARKAT USA, Inc Bis-4-halophenyl-pyrimidines and -1,2,4,5-tetrazines Alan R. Katritzky, Jadwiga Soloducho, and Sergei Belyakov a Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA b Wroclaw, University of Technology, I-4, Wybrzeze Wyspianskiego 27, Poland c Guilford Pharmaceuticals Inc., 6611 Tributary Street, Baltimore, Maryland 21224 E-mail: katritzky@chem.ufl.edu
TL;DR: In this article, N-substituted 2-(benzotriazol-1-yl) [isoindoles and pyrroles] are effected by reactions of primary amines with o-phthalaldehyde and 2,5-dimethoxy-2,5dihydrofuran, respectively, in the presence of benzotriaxole.
Abstract: Efficient one step syntheses of N-substituted-2-(benzotriazol-1-yl) [isoindoles and pyrroles] are effected by reactions of primary amines with o-phthalaldehyde and 2,5-dimethoxy-2,5dihydrofuran, respectively, in the presence of benzotriazole. Reaction of 2,5-dimethoxy-2,5dihydrofuran with benzotriazole gave 2-(benzotriazol-1-yl)furan.
TL;DR: In this article, the utility of α-benzotriazolylenamines as stable alternatives to α-haloenamines was demonstrated by the successful reaction of N-(1-(2H-1,2,3,benzOTriazol-2-yl)-2-methylprop-1- enyl)-N-methylaniline (5a) with phenylethynylzinc chloride to form N-methyl-N-(2methyl-n-(2- phenylethsynyl)-1-propenyl)anil
Abstract: Synthetic routes to and utility of α-benzotriazolylenamines have been explored. α- Benzotriazolylenamines 3a-g, 4a-f and 5a,b were successfully synthesized (i) from N-(trans- buten-1-yl)-N-methylaniline (2) by reaction with 1-chloro-1H-1,2,3-benzotriazole, followed by base induced elimination of HCl and (ii) from amides 1a-g using benzotriazole, POCl3 and NEt3 in CH3CN. The utility of 3a-g, 4a-f and 5a,b as stable alternatives to α-haloenamines was demonstrated by the successful reaction of N-(1-(2H-1,2,3-benzotriazol-2-yl)-2-methylprop-1- enyl)-N-methylaniline (5a) with phenylethynylzinc chloride to form N-methyl-N-(2-methyl-1-(2- phenylethynyl)-1-propenyl)aniline (7).