This review summarizes for the first time the literature data on the use of aliphatic and (hetero)aromatic γ-halo-α,β-unsaturated ketones in the synthesis of heterocycles containing one or several heteroatoms in the ring and their annulated analogs. Heterocyclization methods are organized depending on the reaction mechanism. Bibliography contains 122 sources and covers publications up to 2020.

Ключевые слова: азосочетание; 2-арилгидразоны β-дикетонов; кватернизация С помощью реакции Яппа-Клингемана впервые синтезированы 2-арилгидразоны 1R-3-(4-пиридинил)-1,2,3-пропантрионов.Для них характерно кето-гидразонное строение, но поскольку исходное дикарбонильное соединение несимметрично, реально возможно образование двух таутомерных форм, в одной из которых акцептором водородной связи выступает фрагмент с ацетильной группой (форма А), а в другой -с 4-пиридоильной (форма В).В твердом состоянии 2-арилгидразоны 1R-3-(4-пиридинил)-1,2,3-пропантрионов находятся в форме таутомера А. В твердом состоянии методом ИК-спектроскопии в интервале 1500-1600 см -1 , где наблюдается интенсивное поглощение, была исследована структура как исходных 1R-3-(4-пиридинил)-1,3-пропандионов, так и полученных из них 2-арилгидразонов 1R-3-(4-пиридинил)-1,2,3-пропантрионов.В этой части спектра картина поглощения гидразонов отличается от стартовых соединений.Появляются характерные интенсивные полосы при 1508-1516 см -1 и 1640-1665 см -1 .При этом ни одна из карбонильных групп 2-арилгидразонов 1R-3-(4-пиридинил)-1,2,3-пропантрионов не енолизирована.В растворе присутствуют обе формы А и В. Соотношение форм контролируется природой растворителя.В CDCl 3 у всех соединений содержание изомера А существенно выше, чем изомера В. А в спектре 1-(4-пиридинил)-1,2,3бутантрион-2-[(4-метилфенил)гидразона) вообще отсутствуют сигналы, которые могут быть отнесены к изомеру B. Это свидетельствует о доминирующей координации водородной связи по фрагменту с ацетильной группой и образовании прочных внутримолекулярных водородных связей.В полярном растворителе (DMSO-d 6 ) соотношение изомеров в растворе изменяется в сторону накопления более полярного минорного таутомера В. Проведена оценка факторов, влияющих на положение равновесия.При этом определена зависимость между электронным эффектом заместителя в пара-положении фенилгидразонного фрагмента и соотношением и характеристиками изомеров А и В. Внутримолекулярная водородная связь становится прочнее в случае присутствия электронодонорных заместителей, а термодинамическая выгодность таутомера А возрастает.Кватернизация 2-арилгидразонов 1R-3-(4-пиридинил)-1,2,3пропантрионов йодистым метилом проходит исключительно по пиридиновому атому азота и тем самым уменьшает содержание соединений производных от минорного таутомера В.

ChemInformVolume 44, Issue 46 Heterocyclic Compounds ChemInform Abstract: Synthesis of (Benzo)thiazolo[3,2-a]pyridine Derivatives. A. V. Shelepyuk, A. V. Shelepyuk Taras Shevchenko Natl. Univ., Kiev 01601, UkraineSearch for more papers by this authorL. M. Potikha, L. M. Potikha Taras Shevchenko Natl. Univ., Kiev 01601, UkraineSearch for more papers by this authorV. A. Kovtunenko, V. A. Kovtunenko Taras Shevchenko Natl. Univ., Kiev 01601, UkraineSearch for more papers by this author A. V. Shelepyuk, A. V. Shelepyuk Taras Shevchenko Natl. Univ., Kiev 01601, UkraineSearch for more papers by this authorL. M. Potikha, L. M. Potikha Taras Shevchenko Natl. Univ., Kiev 01601, UkraineSearch for more papers by this authorV. A. Kovtunenko, V. A. Kovtunenko Taras Shevchenko Natl. Univ., Kiev 01601, UkraineSearch for more papers by this author First published: 24 October 2013 https://doi.org/10.1002/chin.201346153Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Volume44, Issue46November 12, 2013 RelatedInformation

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A convenient method is proposed for the preparation of new derivatives of free heterocyclic bases of imidazo[1,2-a]pyridine, pyrido[1,2-a]benzimidazole, and [1,2,4]triazolo[4,3-a]pyridine series. This method entails the dealkylation of N-(2-cyanoethyl)- or N-benzylazolopyridinium quaternary salts in the presence of bases and reaction with ammonium formate in the presence of Pd/C, respectively.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

A new method is proposed for the preparation of 1-hydroxypyrido[1,2-b]isoquinolinium bromides by intramolecular aromatic electrophilic substitution in 3-hydroxy-1-(2-formylbenzyl)pyridinium, 3-hydroxy- and 3-amino-1-[2-(4-chlorobenzoyl)benzyl]pyridinium bromides. The alkylation of pyridine and some of its derivatives by 2-(bromomethyl)benzaldehyde, 2-(bromomethyl)benzophenone derivatives, and methyl 2-(bromomethyl)benzoate was studied.

A new method is proposed for the preparation of N-(2-aminophenyl)isoindoles by the reaction of o-(bromomethyl)benzophenones with 1,2-phenylenediamines. The reaction of N-(2-aminophenyl)isoindoles with Ac2O leads to 1,N-diacetyl- or 1,N,N-triacetyl derivatives, whereas heating with formic acid or diethyl oxalate leads to cyclization with the formation of 11-arylisoindolo[2,1-a]quinoxaline derivatives. Salt formation in the 11-arylisoindolo[2,1-a]quin-oxaline series was studied.

The alkylation of 1-alkyl-2-methyl-1H-imidazoles, 1,2-dimethyl-1H-benzimidazole, and 2-R-pyridines by (4Z)-5-(bromomethyl)-2,2,6,6-tetramethylhept-4-en-3-one gives 1-alkyl-3-[(2Z)-2-tert-butyl-5,5-di-methyl-4-oxohex-2-en-1-yl]-2-methyl-1H-imidazol-3-ium, -1H-benzimidazol-3-ium, and 2-R-pyridinium bromides. Heating solutions of these diazolium salts in ethanol with potassium carbonate leads to 1,5-dihydroimidazo[1,2-a]azepinium and 5,10-dihydroazepino[1,2-a]benzimidazolium derivatives, while heating the pyridinium salts with triethylamine leads to indolizine derivatives. Heating solutions of quaternary salts derived from 1,2-dimethyl-1H-imidazole and 2-methylpyridine in acetic anhydride gives allylic rearrangement products, namely, 3-[(2Z)-2-tert-butyl-5,5-dimethyl-4-oxohex-1-en-1-yl]-1,2-dimethyl-1H-imidazol-3-ium and -2-methylpyridinium bromides, which under the action of base (MeONa for the diazolium salt and Et3N for the pyridinium salt) are converted into 1,5-dihydroimid-azo[1,2-a]azepinium and indolizine derivatives, respectively.

Alkyl derivatives of 1H-imidazo[1,2-a]pyridin-4-ium, 5H-pyrido[1,2-a]benzimidazol-10-ium, 1H-[1,2,4]triazolo[4,3-a]pyridin-4-ium, and 3-methylthiazolo[3,2-a]pyridin-4-ium bromides were obtained in two stages from (4Z)-5-(bromomethyl)-2,2,6,6-tetramethylhept-4-en-3-one, 5-bromo-4-methylpent-3-en-2-one, or (3E)-5-bromopent-3-en-2-one by alkylation of 1-alkyl-1H-imidazoles, 1-alkyl-1H-benzimidazoles, 1-methyl-1H-1,2,4-triazole, and 4-methylthiazole and subsequent cyclization of the quaternary azolium salts in the presence of bases.

On interacting 2-(chloromethyl)-, 2-(bromomethyl)benzonitrile or methyl 2-(bromomethyl)benzoate with 1-R-1H-imidazoles and 1-R-1H-benzimidazoles quaternary diazolium salts are formed, the heating of which with bases (K2CO3, Et3N) led to the intramolecular acylation products, 1-alkyl-10-amino-1H-imidazo[1,2-b]isoquinolin-4-ium halides, 5-alkyl-6-amino-5H-benzimidazo[1,2-b]isoquinolin-12-ium halides, or 1-alkyl-1H-imidazo[1,2-b]isoquinolin-4-ium-10-olate halides.

The reaction of 3-NHR-isoquinolin-1(2H)-ones (R = Ar) with aromatic aldehydes in the presence of Me3SiCl or in acetic acid leads to the formation of derivatives of dibenzo[b,f][1, 8]naphthyridin-5(6H)- one and benzo[f]isoquino[3,4-b][1, 8]naphthyridine-5,9(6H,7H)-dione. The reaction for R = Het in the presence of Me3SiCl gives derivatives of 5H-pyrido[1',2':1,2]pyrimido[4,5-c]isoquinolin-5-one, benzo[f]isoquinoline[3,4-b][1,8]naphthyridine-5,9[6H,7H]-dione, and derivatives of new heterocyclic systems, 5H-pyrazino[1',2':1,2]pyrimido[4,5-c]isoquinolin-5-one, 5H-[1,3]thiazolo[3',2':1,2]pyrimido- [4,5-c]isoquinolin-5-one, 5-H-benzo[f]pyrazolo[3,4-b][1,8]naphthyridin-5-one, and isoquino[3,4-b]- [1,5]naphthyridin-5(6H)-one. The effect of the structure of substituent R and nature of the substituent in the benzaldehydes on the structure of the reaction products was studied.

A novel method is proposed for the preparation of azolo[b]isoquinolines based on the alkylation of N-alkyl-1,3-diazoles or 1,3-thiazole derivatives using [2-(bromomethyl)phenyl](phenyl)methanone with subsequent cyclization of the quaternary azolium salts in the presence of base. The 10(11)-hydroxy derivatives of the 5,10-dihydro-1H-imidazo[1,2-b]isoquinolinium, 6,11-dihydro-5H-benzimidazo-[1,2-b]isoquinolinium, 5,10-dihydro-1H-[1, 2, 4]triazolo[4,3-b]isoquinolinium, or 5,10-dihydro[1, 3]-thiazolo[3,2-b]isoquinolinium bromides obtained in this way readily lose a molecule of water upon heating with HBr or Ac2O to give the corresponding quasi-aromatic azolo[b]isoquinolinium salts.

The alkylation of derivatives of 3-aminoisoquinolin-1(2H)-one in the presence of NaH may proceed in three directions: 1) at the carbonyl group oxygen atom, 2) at the nitrogen atom N-2, and 3) at the 3-amino group. The reaction of equivalent amounts of the reagents gives predominantly products of substitution at the 3-amino group. Repeated alkylation proceeds at the lactam fragment to give a mixture of O-alkyl and N-alkyl derivatives. Acylation of 3-dialkylamino- and 3-alkylanilinoisoquinolin-1(2H)-ones in the presence of NaH gave derivatives of 3-amino-1-isoquinolinyl 4-ethoxybenzoate.

Cyclization of 1-alkyl-3-[(2Z)-2,4-diaryl-4-oxobut-2-en-1-yl]-1H-benzimidazol-3-ium bromides occurs in the presence of MeONa at a reduced temperature of 5–10°C via a 1,5-electrocyclization mechanism to give 3a,4-dihydro-3H-pyrrolo[1,2-a]benzimidazoles. These are unstable under the reaction conditions and are readily converted to {1-[2-(alkylamino)phenyl]-4-phenyl-1H-pyrrol-3-yl}(phenyl)methanones.

AbstractThe reaction of 3‐aminoisoquinolinone derivatives with aromatic aldehydes in the presence of Tms‐Cl leads to the formation of fused naphthyridine and isoquinolinone derivatives.

Fusion of 4-bromo-1,3-diphenyl-2-buten-1-ones (γ-bromodypnones) with 1,2-dimethyl-1H-benzimidazole and further treatment of the reaction product with a base (morpholine) gives 7,9-diaryl-5-methyl5,10-dihydroazepino[1,2-a]benzimidazol-11-ium bromides. The reaction of γ-bromodypnone with 1-alkyl-2-methyl-1H-imidazoles in benzene at 25 °C gives quaternary azolium salts. Upon heating their solutions in alcohol in the presence of K2CO3 the latter cyclize to 1-R-6,8-diaryl-1,5-dihydroimidazo[1,2-a]azepin-4-ium bromides or 1-R-6,8-diaryl-1H-imidazo[1,2-a]azepines depending on the nature of the substituent in the benzene rings and the substituent at the N(1) atom of the imidazole.

2-Arylmethyl- and 2-arylmethyl-3-methyl-substituted 3,4-dihydrothieno[3,4-d]pyrimidin-4-ones were synthesized starting from 2-cyanomethylbenzoic acid and methyl 3-amino-4-thiophenecarbonate, obtained in situ from its hydrochloride by a new method which gives an increased yield of the desired products. The physicochemical properties and the biological potential of the compounds synthesized have been compared with analogous substituted 2,3-dimethylthieno[2,3-d][pyrimidinones, thieno[3,2-d]pyrimidinones, and their benzene isosteres. The differences associated with the position of the sulfur atom, are most clearly reflected in the electronic spectra. On the basis of calculated data, the transition from derivatives of 4-oxo-3,4-benzopyrimidines to their analogous thieno isosteres leads to changes in the profiles of their biological activities.

A method for the synthesis of derivatives of [1, 3]thiazolo[3,2-a]pyridines, pyrido[2,1-b][1, 3]benzo-thiazole, [1, 3, 4]thiadiazolo[3,2-a]pyridine, and [1, 2, 4]triazolo[4,3-a]pyridine, which includes base initiated cyclization of quaternary azolium salts, formed by the interaction of (Z)-1,3-diaryl-4-bromo-2-buten-1-ones with 1-alkyl-1H-1,2,4-triazoles, 4-methyl-1,3-thiazole, 1,3-benzothiazole, and N-phenyl-1,3,4-thiadiazole-2-amine. Derivatives of 2-chloroimidazo[1,2-a]pyridine were obtained when 5-chloro-1-methyl-1H-imidazole was used.