Mikhail Krayushkin - Academia.edu (original) (raw)
Papers by Mikhail Krayushkin
Synthesis, 2018
A new chemoselective method for the synthesis of 2-aryl-1,3-oxazoles by deoxygenation of the corr... more A new chemoselective method for the synthesis of 2-aryl-1,3-oxazoles by deoxygenation of the corresponding N-oxides has been developed. As the deoxygenation reagent, a previously unknown complex of collidine with phosphorus trichloride in a 2:1 ratio has been used. The developed method enabled the preparation of a wide range of 2-aryl-1,3-oxazoles comprising various functional groups in good yields. The advantage of this reagent is its tolerance to nitro, methyl, hydroxyl, formyl, and acetyl groups, and double bonds. Due to chemoselectivity and availability of reagents, the method may be used for deoxygenation of N-oxides of other heterocyclic compounds (thiazole, pyridine, quinoline, etc.).
Russian Journal of Organic Chemistry, 2004
A procedure was developed for the synthesis of bis(2,5-dimethyl-3-thienyl)ethenes with partially ... more A procedure was developed for the synthesis of bis(2,5-dimethyl-3-thienyl)ethenes with partially fixed molecular conformation, and their photochromic properties in solution were studied.
![Research paper thumbnail of Fotochromic Dihetarylethenes: XIX. Synthesis of 1,2-Dihetarylethenes with 2,5-Dihydrothiophene Bridge from Thieno[3,2-b]pyrroles](https://attachments.academia-assets.com/93370331/thumbnails/1.jpg)
](Russian Journal of Organic Chemistry, 2003
Reductive cyclization by McMurry method was performed with diketosulfide obtained by treating wit... more Reductive cyclization by McMurry method was performed with diketosulfide obtained by treating with Na 2 S of compound prepared by regioselective acylation of methyl 2-methyl-4H-thieno[3,2-b]pyrrole-5-carboxylate with chloroacetyl chloride. As a result was synthesized a photochromic 1,2-dihetarylethene where the fuzed rings are connected by a 2,5-dihydrothiophene ring. The oxidation of the latter provides 2,5-dihydrothiophene-1,1-dioxide bridge.
Russian Chemical Bulletin, 2004
The reactions of monothiooxamides with О methylhydroxylamine were studied. Depend ing on the subs... more The reactions of monothiooxamides with О methylhydroxylamine were studied. Depend ing on the substituents in monothiooxamides, the reactions result in the formation of hydroxamic acid derivatives or various N methoxy derivatives of amidoximes.
Russian Chemical Bulletin, 2004
A convenient method for the synthesis of monothiooxamides by the reaction of chloro acetamides wi... more A convenient method for the synthesis of monothiooxamides by the reaction of chloro acetamides with a solution of elemental sulfur in amines was developed.
Journal of Sulfur Chemistry, 2009
ABSTRACT Dihydrothiazoles and thiazoles were synthesized by the reaction of monothiooxamides cont... more ABSTRACT Dihydrothiazoles and thiazoles were synthesized by the reaction of monothiooxamides containing allylamine and propargylamine fragments with halogens in ionic liquids.
Chemistry of Heterocyclic Compounds, 2003
Thiadiazole derivatives R 0300 Synthesis of 4,5-Dihydro-1,3,4-thiadiazole-2-carboxamide and 2-Car... more Thiadiazole derivatives R 0300 Synthesis of 4,5-Dihydro-1,3,4-thiadiazole-2-carboxamide and 2-Carbamoyl-4,5-dihydro-1,3,4-thiadiazole 1-Oxide Derivatives Based on Hydrazones of Oxamic Acid Thiohydrazides.-Acylation of accessible hydrazones of oxamic acid thiohydrazides (I) provides access to dihydrothiadiazoles (VI) (7 examples), which can be easily converted to corresponding S-oxides (VII) upon oxidation with H2O2.
![Research paper thumbnail of Synthesis of first spiropyrans and spirooxazines based on thieno[3,2-b]pyrroles](https://attachments.academia-assets.com/89702629/thumbnails/1.jpg)
](Russian Chemical Bulletin, 2004
Russian Chemical Bulletin, 2004
Regioselective C or O alkylation of alkyl 4 hydroxy 2 methylthiophene 3 carboxylates with α halo ... more Regioselective C or O alkylation of alkyl 4 hydroxy 2 methylthiophene 3 carboxylates with α halo ketones is possible, depending on the solvent nature. A convenient preparative method of C alkylation was proposed and previously not easily accessible β hydroxythiophene derivatives were synthesized.
Bulletin of the Academy of Sciences of the USSR Division of Chemical Science, 1971
Russian Chemical Bulletin
ABSTRACT An approach to the synthesis of earlier unknown substituted 6-aryl-6,7-dihydro-2H-imidaz... more ABSTRACT An approach to the synthesis of earlier unknown substituted 6-aryl-6,7-dihydro-2H-imidazo[5,1-c][1,2,4]triazole-3,5-diones was developed, which is based on the reaction of 5-arylaminomethyl-2,4-dihydro[1,2,4]triazol-3-ones with 1,1′-carbonyldiimidazole. The structure of one of the products was unambiguously established by X-ray diffraction analysis.
Russian Chemical Bulletin
ABSTRACT A new convenient method for the synthesis of earlier unknown 2-substituted derivatives o... more ABSTRACT A new convenient method for the synthesis of earlier unknown 2-substituted derivatives of 5-phenylaminomethyl-2,4-dihydro-3H-[1,2,4]triazol-3-ones was developed. The method involved the alkaline hydrolysis of 2-alkyl-6-phenyl-6,7-dihydro-3H-imidazo[5,1-c][1,2,4]-triazole-3,5(2H)-diones obtained by alkylation of 6-phenyl-6,7-dihydro-2H-imidazo[5,1-c]-[1,2,4]triazole-3,5(2H)-diones.
ChemInform
ABSTRACT
ChemInform
Some Reactions of Pyridinium Salts Derived from Trichloromethylarenes with N-and C-Nucleophiles.-... more Some Reactions of Pyridinium Salts Derived from Trichloromethylarenes with N-and C-Nucleophiles.-The reaction of pyridinium salts derived from 1-trichloromethyl-2,4,6-trimethylbenzene with N-nucleophiles such as (II) and C-nucleophiles such as indole proceeds through hetarylation furnishing 4-substituted pyridines [cf. (III), (V)].-(BELEN'KII, L. I.; POD
ChemInform
Reactions of Cyclic Enaminoketones with Benzylidenemalononitriles. Synthesis of New Fused Heteroc... more Reactions of Cyclic Enaminoketones with Benzylidenemalononitriles. Synthesis of New Fused Heterocyclic Systems Containing the 1,4-Dihydropyridine Fragment.-Reactions of N-hetaryl-substituted enaminoketones with benzylidenemalononitriles (IV) give rise to new heterocyclic structures in which a 1,4-dihydropyridine ring is fused to furopyrimidine [cf. (V)] or thienopyrimidine [cf. (VIII), (IX)] fragments.-(LICHIT
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy, Jan 5, 2018
Six new photoactive unsymmetrical diarylethenes bearing thiazole ring with hydrogen at the reacti... more Six new photoactive unsymmetrical diarylethenes bearing thiazole ring with hydrogen at the reactive carbon atom have been synthesized. Their structures have been studied by DFT calculations and X-ray crystallography. All compounds undergo irreversible photochemical transformations under irradiation with ultraviolet light, proceeding through the photocyclization stage. It has been found that only some normal (thiophene, imidazole and pyrazole derivatives) and inverse type (oxazole derivative) diarylethenes form colored photoinduced isomers under UV. In polar acetonitrile these intermediates show relatively fast irreversible thermal reaction, while in nonpolar toluene slow cycloreversion to initial diarylethenes is the predominant process of these species.
Synthesis, 2018
A new chemoselective method for the synthesis of 2-aryl-1,3-oxazoles by deoxygenation of the corr... more A new chemoselective method for the synthesis of 2-aryl-1,3-oxazoles by deoxygenation of the corresponding N-oxides has been developed. As the deoxygenation reagent, a previously unknown complex of collidine with phosphorus trichloride in a 2:1 ratio has been used. The developed method enabled the preparation of a wide range of 2-aryl-1,3-oxazoles comprising various functional groups in good yields. The advantage of this reagent is its tolerance to nitro, methyl, hydroxyl, formyl, and acetyl groups, and double bonds. Due to chemoselectivity and availability of reagents, the method may be used for deoxygenation of N-oxides of other heterocyclic compounds (thiazole, pyridine, quinoline, etc.).
Russian Journal of Organic Chemistry, 2004
A procedure was developed for the synthesis of bis(2,5-dimethyl-3-thienyl)ethenes with partially ... more A procedure was developed for the synthesis of bis(2,5-dimethyl-3-thienyl)ethenes with partially fixed molecular conformation, and their photochromic properties in solution were studied.
Russian Journal of Organic Chemistry, 2003
Reductive cyclization by McMurry method was performed with diketosulfide obtained by treating wit... more Reductive cyclization by McMurry method was performed with diketosulfide obtained by treating with Na 2 S of compound prepared by regioselective acylation of methyl 2-methyl-4H-thieno[3,2-b]pyrrole-5-carboxylate with chloroacetyl chloride. As a result was synthesized a photochromic 1,2-dihetarylethene where the fuzed rings are connected by a 2,5-dihydrothiophene ring. The oxidation of the latter provides 2,5-dihydrothiophene-1,1-dioxide bridge.
Russian Chemical Bulletin, 2004
The reactions of monothiooxamides with О methylhydroxylamine were studied. Depend ing on the subs... more The reactions of monothiooxamides with О methylhydroxylamine were studied. Depend ing on the substituents in monothiooxamides, the reactions result in the formation of hydroxamic acid derivatives or various N methoxy derivatives of amidoximes.
Russian Chemical Bulletin, 2004
A convenient method for the synthesis of monothiooxamides by the reaction of chloro acetamides wi... more A convenient method for the synthesis of monothiooxamides by the reaction of chloro acetamides with a solution of elemental sulfur in amines was developed.
Journal of Sulfur Chemistry, 2009
ABSTRACT Dihydrothiazoles and thiazoles were synthesized by the reaction of monothiooxamides cont... more ABSTRACT Dihydrothiazoles and thiazoles were synthesized by the reaction of monothiooxamides containing allylamine and propargylamine fragments with halogens in ionic liquids.
Chemistry of Heterocyclic Compounds, 2003
Thiadiazole derivatives R 0300 Synthesis of 4,5-Dihydro-1,3,4-thiadiazole-2-carboxamide and 2-Car... more Thiadiazole derivatives R 0300 Synthesis of 4,5-Dihydro-1,3,4-thiadiazole-2-carboxamide and 2-Carbamoyl-4,5-dihydro-1,3,4-thiadiazole 1-Oxide Derivatives Based on Hydrazones of Oxamic Acid Thiohydrazides.-Acylation of accessible hydrazones of oxamic acid thiohydrazides (I) provides access to dihydrothiadiazoles (VI) (7 examples), which can be easily converted to corresponding S-oxides (VII) upon oxidation with H2O2.
Russian Chemical Bulletin, 2004
Russian Chemical Bulletin, 2004
Regioselective C or O alkylation of alkyl 4 hydroxy 2 methylthiophene 3 carboxylates with α halo ... more Regioselective C or O alkylation of alkyl 4 hydroxy 2 methylthiophene 3 carboxylates with α halo ketones is possible, depending on the solvent nature. A convenient preparative method of C alkylation was proposed and previously not easily accessible β hydroxythiophene derivatives were synthesized.
Bulletin of the Academy of Sciences of the USSR Division of Chemical Science, 1971
Russian Chemical Bulletin
ABSTRACT An approach to the synthesis of earlier unknown substituted 6-aryl-6,7-dihydro-2H-imidaz... more ABSTRACT An approach to the synthesis of earlier unknown substituted 6-aryl-6,7-dihydro-2H-imidazo[5,1-c][1,2,4]triazole-3,5-diones was developed, which is based on the reaction of 5-arylaminomethyl-2,4-dihydro[1,2,4]triazol-3-ones with 1,1′-carbonyldiimidazole. The structure of one of the products was unambiguously established by X-ray diffraction analysis.
Russian Chemical Bulletin
ABSTRACT A new convenient method for the synthesis of earlier unknown 2-substituted derivatives o... more ABSTRACT A new convenient method for the synthesis of earlier unknown 2-substituted derivatives of 5-phenylaminomethyl-2,4-dihydro-3H-[1,2,4]triazol-3-ones was developed. The method involved the alkaline hydrolysis of 2-alkyl-6-phenyl-6,7-dihydro-3H-imidazo[5,1-c][1,2,4]-triazole-3,5(2H)-diones obtained by alkylation of 6-phenyl-6,7-dihydro-2H-imidazo[5,1-c]-[1,2,4]triazole-3,5(2H)-diones.
ChemInform
ABSTRACT
ChemInform
Some Reactions of Pyridinium Salts Derived from Trichloromethylarenes with N-and C-Nucleophiles.-... more Some Reactions of Pyridinium Salts Derived from Trichloromethylarenes with N-and C-Nucleophiles.-The reaction of pyridinium salts derived from 1-trichloromethyl-2,4,6-trimethylbenzene with N-nucleophiles such as (II) and C-nucleophiles such as indole proceeds through hetarylation furnishing 4-substituted pyridines [cf. (III), (V)].-(BELEN'KII, L. I.; POD
ChemInform
Reactions of Cyclic Enaminoketones with Benzylidenemalononitriles. Synthesis of New Fused Heteroc... more Reactions of Cyclic Enaminoketones with Benzylidenemalononitriles. Synthesis of New Fused Heterocyclic Systems Containing the 1,4-Dihydropyridine Fragment.-Reactions of N-hetaryl-substituted enaminoketones with benzylidenemalononitriles (IV) give rise to new heterocyclic structures in which a 1,4-dihydropyridine ring is fused to furopyrimidine [cf. (V)] or thienopyrimidine [cf. (VIII), (IX)] fragments.-(LICHIT
Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy, Jan 5, 2018
Six new photoactive unsymmetrical diarylethenes bearing thiazole ring with hydrogen at the reacti... more Six new photoactive unsymmetrical diarylethenes bearing thiazole ring with hydrogen at the reactive carbon atom have been synthesized. Their structures have been studied by DFT calculations and X-ray crystallography. All compounds undergo irreversible photochemical transformations under irradiation with ultraviolet light, proceeding through the photocyclization stage. It has been found that only some normal (thiophene, imidazole and pyrazole derivatives) and inverse type (oxazole derivative) diarylethenes form colored photoinduced isomers under UV. In polar acetonitrile these intermediates show relatively fast irreversible thermal reaction, while in nonpolar toluene slow cycloreversion to initial diarylethenes is the predominant process of these species.