Nitrosochlorination reaction of substituted imidazolin-2-ones

Interaction of nitrosyl chloride with 1-arylimidazolin-2-ones in methanol leads to the formation of 4,5-dimethyoxyimidazolidin-2-ones. Under similar conditions 1,5-diarylimidazolin-2-ones give 1,5-diaryl-4-oximino-5-alkoxyimidazolidin-2-ones. When the reaction is carried out in an aprotic solvent 1,5-diaryl-4-nitrosoimidazolin-2-ones are separated, and when treated with alcohol they give the final reaction products. An increase in temperature and duration of the reaction results in the formation of 1,5-diaryl-5-hydroxyhydantoins.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1339–1342, October, 1986.     

The synthesis of methyl 2-(benzyloxycarbonyl)amino-3-dimethylaminopropenoate. The synthesis of trisubstituted pyrroles, 3-amino-2H-pyran-2-ones,fused 2H-pyran-2-ones and 4H-pyridin-4-ones

Methyl 2-(benzyloxycarbonyl)aimno-3-dimemylaminopropenoate ( 2 ) was prepared from methyl N-(benzyloxycarbonyl)glycinate ( 1 ) and t-butoxybis(dimethylamino)methane, and used as a reagent for preparation of substituted 3-(benzyloxycarbonyl)amino-4H-quinolizin-4-ones 5 and 6 , ?2H-pyran-2-ones 17–19 , ?2H-1-benzopyran-2-ones 28–31 , and -naphthopyrans 32–35 , ?2H-pyrano[3,2-c]pyridine-2,5-dione 46 , -pyrano-[4,3-b]pyran-2,5-dione 47 , -pyrano[3,2-c]benzopyran-2,5-dione 48 , -pyrano[2,3-c]pyrazol-6-ones 49 and 50 , -pyrano[2,3-d]pyrirnidin-7-ones 51 and 52 derivatives. In the reaction of 2 with 1,3-diketones trisubsti tuted pyrroles 14–16 were formed. Selective removal of benzyloxycarbonyl group was achieved by cat alytic transfer hydrogenation with Pd/C in the presence of cyclohexene to afford free 3-amino compounds 7 , 8 , 20 , 36–38 and 53–57 in yields better than 80%.     

Asymmetric synthesis of spiro 2-pyrrolidin-5-ones, 2-piperidin-6-ones and 1-isoindolin-3-ones. Part 2: N-Acyliminium ion cyclisations with an internal alkene nucleophile

Chiral non-racemic bicyclic and tricyclic oxylactams obtained in two steps from N-(2-hydroxy-1(R)-phenylethyl)-succinimide and phthalimide are cyclised diastereoselectively in formic acid to give spiro[cyclohexane-1,2′-pyrrolidin]-5-ones and spiro[cyclohexane-1,1′-isoindolin]-3-ones, respectively.     

Synthesis of Novel 2-Iminothiazolidin-4-ones

Abstract

Thiazolidin-4-ones are known to exhibit diverse biological activities such as antimicrobial, anticancer, antidiarrheal, anticonvulsant, antidiabetic, antihistaminic, and antifungal activities. In the present investigation, a series of 2-haloacetamides was prepared by reacting chloroacetyl chloride with amines in dry benzene under reflux conditions. The formed 2-haloacetamides reacted with potassium thiocyanate in refluxing dry acetone to afford new 2-iminothiazolidin-4-ones. The 5-arylidene-2-imino-3 (napthalen-2yl)-thiazolidin-4-ones were prepared by condensing 2-iminothiazolidin-4-ones with substituted benzaldehydes. All the products were characterized by infrared, mass, and ¹H and ¹³C NMR techniques.     

Reaction of ketenes with N,N-disubstituted α-aminomethyleneketones. X. Synthesis of N,N-disubstituted 6-alkyl-4-amino-3,3-dichloro-3,4-dihydro-2H-pyran-2-ones and of 6-alkyl-4-amino-3-chloro-2H-pyran-2-ones

Cycloaddition of dichloroketene to N,N-disubstituted 1-amino-4-methyl-1-penten-3-ones and 1-amino-4,4-dimethyl-1-penten-3-ones occurred in moderate to fair yield only in the case of aromatic N-substitution to give N,N-disubstituted 6-alkyl-4-amino-3,3-dichloro-3,4-dihydro-2H-pyran-2-ones, which were dehydrochlorinated with DBN to afford in good yield N,N-disubstituted 6-alkyl-4-amino-3-chloro-2H-pyran-2-ones. In the case of aliphatic N,N-disubstitution, cyclo-addition led directly to 6-alkyl-4-dialkylamino-3-chloro-2H-pyran-2-ones only for N,N-disubstituted 1-amino-4,4-dimethyl-1-penten-3-ones. The reaction between 1-dimethylamino-4-methyl-1-penten-3-one and dichloroketene gave 3-chloro-4-dimethylamino-3,6-dihydro-6-isopropylidene-2H-pyran-2-one in low yield.     

Action of hydrogen peroxide on some 2-aminooxazoles and imidazolin-2-ones. Isolation of hydroperoxyimidazolidin-2-ones

The reaction of some 2-aminooxazoles and imidazolidin-2-ones with hydrogen peroxide afforded stable trans-β-hydroxyhydroperoxy- or dihydroperoxyimidazolidin-2-ones according to the reaction conditions. In the case of 3a-hydroxy-7a-hydroperoxyoctahydro-2H-benzimidazolidin-2-one, the trans isomer is forbidden and cis adduct was isolated. A radical pathway to these hydroperoxides is proposed. From 2-amino-4-methyloxazole and hydrogen peroxide 2-amino-2-hydroxy-4-methyloxazolidin-4-yl peroxyacetate was also isolated.     

Chemistry of 2-methylene-2,3-dihydrofuran-3-ones. 2. 2-Alkoxycarbonylmethylene-5-aryl-4-halo-2,3-dihydrofuran-3-ones: Synthesis,structure, and properties

Reaction of 5-aryl-4-halo-2,3-dihydrofuran-2,3-diones with alkoxycarbonylmethylenetriphenylphosphoranes has given 2-alkoxycarbonylmethylene-5-aryl-4-halo-2, 3-dihydrofuran-3-ones, which readily add halogens at the 2-exocyclic double bond, and on reaction with arylamines recyclize to give 2-hydroxy-2, 3-dihydropyrrol-3-ones.For Communication 1, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1034–1038, August, 1989.     

4-Substituted-3,4-dihydro-3-methyl-2H-1,3-benzoxazin-2-ones. III (2,3). Solvolytic-reductive transformation of 4-(2-keto)-benzoxazin-2-ones into oxazin-2-ones

A series of 4-(2-keto-substituted)-3,4-dihydro-3-methyl-2H-1,3-benzoxazin-2-ones 1 (Table I) was synthesized by condensation of 3-alkyl-3,4-dihydro-4-hydroxy-2H-1,3-benzoxazin-2-ones 4 with ketones 5 having active alpha hydrogens. In the presence of alcoholic potassium borohydride, compounds 1 underwent reductive transacylation to give 1,3-oxazin-2-one derivatives 3 (Table III, a,b,c). When the other side of the ketone possessed substituents other than hydrogen, there were always also normal reduction products, i.e., secondary alcohols 2 (Table II) in addition to 3.     

Mass-spectrometric study of the cyclization of diazo ketones. 1. Cyclization of 1-diazo-3-sulfonylaminopropan-2-ones to N-sulfonylazetidin-3-ones

A comparison of the mass spectra of 1-diazo-3-sulfonylaminopropan-2-ones and N-sulfonylazetidin-3-ones makes it possible to conclude that under the conditions of electron impact and chemical ionization the molecular ions of diazo ketones lose a molecule of nitrogen and undergo partial cyclization to the corresponding azetidinones without undergoing the Wolff rearrangement.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 334–342, March, 1982.     

1,3-oxazines. Intramolecular cyclization of 1-diazo-3-benzamidopropan-2-ones

2-Aryl-5,6-dihydro-4H-1,3-oxazin-5-ones were obtained in the reaction of 1-diazo-3-benzamidopropan-2-ones with acidic agents.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1324–1326, October, 1980.     

One-pot synthesis of benzo[f]quinolin-3-ones and benzo[a]phenanthridein-5-ones by the photoanuulation of 6-chloropyridin-2-ones and 3-chloroisoquinolin-1-ones to phenylacetylene

The one-pot synthesis of benzo[f]quinolin-3-ones and benzo[a]phenanthridein-5-ones was achieved by the inter- and intramolecular photoannulation of 6-chloropyridin-2-ones and 3-chloroisoquinolin-1-ones with phenylacetylene or tethered phenylacetylene. The reactions were proceeded by photoaddition of 6-chloropyridin-2-ones and 3-chloroisoquinolin-1-ones to phenylacetylene to give the chlorine-substituted stilbenoids, and then 6π electrocyclization of the stilbenoids and oxidation aromatization to afford the polycyclic products.     

4,4-Dialkoxybutan-2-ones as Synthons

The review considers the synthetic potential of 4,4-alkoxybutan-2-ones which are promising synthons available from diacetylene-containing industrial gases. The reactivity of 4,4-dialkoxybutan-2-ones toward mono- and difunctional reagents, as well as in cycloaddition processes, is discussed.__________Translated from Zhurnal Organicheskoi Khimii, Vol. 41, No. 1, 2005, pp. 9–32.Original Russian Text Copyright © 2005 by Maretina.     

Acylation of 2-thioxoquinazol-4-ones: Formation of 2-acylthioquinazol-4-ones

The acylation of 2-thioxoquinazol-4-ones by various acylating agents was studied. The main products are 2-benzoylthioquinazol-4-ones. Minor amounts of the N₍₃₎-acylation products are formed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1095–1097, August, 1987.     

Preparation of 1,5-disubstituted pyrrolidin-2-ones

1,5-Disubstituted pyrrolidin-2-ones 18a-g, 19a-h, and 20a-f were synthesized in good to excellent yields via the nucleophilic substitution of 5-(benzotriazol-1-yl)-1-substituted-pyrrolidin-2-ones 9 with allylsilanes, organozinc reagents, and phosphorus compounds. Compounds 9 and 5-(benzotriazol-2-yl)-1-substituted-pyrrolidin-2-one isomers 10 are readily prepared in total 70-84% yields from 2, 5-dimethoxy-2,5-dihydrofuran (7), primary amines 8, and benzotriazole; 9 and 10 react identically with nucleophiles.     

A novel convenient synthesis of 5-acyl-1,2-dihydropyrimidin-2-ones via 4-trichloromethyl-1,2,3,4-tetrahydropyrimidin-2-ones

A novel four-step methodology for the synthesis of 5-acyl-1,2-dihydropyrimidin-2-ones has been developed. The reaction of readily available N-[(1-acetoxy-2,2,2-trichloro)ethyl]ureas with Na-enolates of 1,3-diketones or β-oxoesters followed by heterocyclization-dehydration of the oxoalkylureas formed gave 5-acyl-4-trichloromethyl-1,2,3,4-tetrahydropyrimidin-2-ones. The latter, in the presence of NaH, eliminate CHCl₃ to give the target compounds.     

Synthesis of 3-S-hetaryl-substituted pyridin-2(1H)-ones and 5,6-dihydropyridin-2(1H)-ones*

A method has been developed for the synthesis of 3-S-hetaryl-substituted pyridin-2(1H)-ones and 5,6-dihydropyridin-2(1H)-ones based on the base catalyzed cyclization of N-(3-oxoalkyl)- and N-(3-oxoalkenyl)amides which contain a divalent sulfur atom in an α-position to a carbamoyl group and bound to the heterocycle.     

Reaction of piperidine and morpholine with 2H-pyran-2-ones, 2H-thiopyran-2-ones, 2H-pyran-2-thiones,and 2H-thiopyran-2-thiones. A novel route to thiophene derivatives

The reaction of piperidine or morpholine with 2H-pyran-2-ones was found to give open chain δ-oxoamides, while with 2H-thiopyran-2-ones, thiophene derivatives were formed. For 2H-pyran-2-thiones, either open chain δ-oxothioamides or thiophene derivatives were obtained. From the ¹ H nmr data of the pyran derivatives, the effect of the replacement of ring and carbonyl oxygens with sulphur on the chemical shift of the H-3 proton could be studied.     

Reactivity of pyrrol-2-ones. (review)

Published data on the chemical transformations of pyrrol-2-ones are reviewed and analyzed. The extensive synthetic possibilities of compounds containing a pyrrolone ring in the synthesis of various heterocyclic compounds with complex structures are demonstrated. The reactions are arranged according to the reaction centers of the pyrrol-2-ones: The methylene unit, the C=C double bond, the electron-deficient carbon atom of the carbonyl group.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1463, October, 2004.     

Synthesis of imidazolin-2-ones by rearrangement of N-carbamoyliminium salts derived from 4-hydroxyimidazolidin-2-ones

The action of trifluoroacetic acid on 4-hydroxyimidazolidin-2-ones 9a,b,c induces the formation of N-carbamoyliminium salts 10a,b,c which rearrange to imidazolin-2-ones 11a,b,c. The reactions proceed in high yield at ambient temperatures.     

1,4,5,6-Tetrahydro-1,2,4-triazin-6-ones and 3-amino-1-imidazolin-4-ones from 2-aminoacylhydrazines

The 2-aminoacylhydrazines form 1,4,5,6-tetrahydro-1,2,4-triazin-6-ones with orthoesters and iminoesters. Benzylidene and isopropylidene derivatives of the 2-aminoacylhydrazines give the corresponding derivatives of 3-amino-1-imidazolin-4-ones with the same reagents.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1388–1391, October, 1991.