5-Substituted 2-methyl- and 2-methyleneindolines

A method for the synthesis of 5-substituted 1,3,3-trimethyl-2-methyleneindolines has been developed, in which the substituents are introduced into the benzene ring of 1,2,3,3-tetramethylindolines, followed by oxidation.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1474–1477, November, 1986.     

Substituted 2-methyl-and 2-methyleneindolines 4. Hetaryl-condensed 2-methyl- and 2-methyleneindolines with a linear structure

Methods have been developed for the synthesis from amino-substituted indolines of first linear trinuclear hetaryl-condensed2-methyleneindolines having quinolone, quinoline, quinoxaline, and benzmidazole fragments. The structure of the obtained compounds was confirmed by ¹H and ¹³C NMR spectra.For communication 3, see [1]Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1331–1335, October, 1992.     

5-Benzopyridyl-substituted 2-methyl- and 2-methyleneindolines

A method of synthesis of 5-(isoquinol-l-yl)- and 5-(quinol-2-yl)-1,3,3-trimethyl-2-methyleneindolines has been developed consisting of hetarylation of 1,2,3,3-tetra-methylindoline with isoquinoline and quinoline in the presence of benzoyl chloride, followed by oxidation and aromatization of N-benzoyl-1,2-dihydrobenzopyridine derivatives of 1,2,3,3-tetramethylindoline formed at the first stage to 5-benzopyridyl-substituted 2-methylene-indolines.For a preliminary communication on this subject, see [15].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1367–1372, October, 1989.     

Substituted 2-methyl- and 2-methyleneindolines. 2. Nitro- and amino-substituted 2-methyl- and 2-methylene-indolines

From 5- and 6-aminotetramethylindolines, 2-methyleneindolines have been synthesized; these compounds can be condensed with other heterocyclic systems. The nitration of 1,2,3,3-tetramethylindoline under different conditions was studied.For communication 1, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 919–923, July, 1989.     

Substituted 2-methyl- and 2-methyleneindolines. 6. Adducts of dialkylphosphites with 1,3,3-trimethyl-2-methyleneindoline. Reagents for synthesizing 5-substituted 2-methyl- and 2-methyleneindolines

The readily formed addition products of dialkylphosphites and 1,3,3-trimethyl-2-methyleneindoline have been used to synthesize 1,2,3,3-tetramethyl-3H-indolium salts and their derivatives substituted in the benzene ring. In most cases the protecting phosphorus group can be readily removed by adding mineral acids.For Communication 5, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1049–1054, August, 1993.     

5-Hetaryl-substituted 2-methyleneindolines and polymethine dyes based on them

2-Methyleneindolines containing benzazole residues at the 5-position were synthesized and polymethine dyes were obtained from them. The bathochromic shifts induced by the introduction of heterocyclic residues into indocyanines exceed the similar shifts induced by the same heterocycles in thio and quinocyanines.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1050–1054, August, 1990.     

Synthesis and properties of polymers containing sprio(indoline-isoxazoline)

Polymers containing spiro(indoline-isoxazoline) nuclei were prepared by 1,3-dipolar cycloaddition reactions of N,N′-alkylene-bis-3,3-dimethyl-2-methyleneindolines with bis-hydroxamic chlorides. Irradiation of the polymers with UV in solution resulted in novel skeletal rearrangements and resulted in polymers containing benzo-1,5-diazocine-2-one nuclei. Photoconductivities of the polymers were also studied.     

Synthesis of 2-methyl-4,6-diarylpyrilium tetrafluoroborates

Condensation of acetophenones with acetic anhydride in the presence of boron trifluoride etherate has given some 2-methyl -4,6-diarylpyrilium tetrafluoroborates. The optimum conditions for the synthesis of 2-methyl-substituted pyrilium salts have been established.Translated from Khimiya Geterotsiklicheskikh Soedenii, No. 2, pp. 173–176, February, 1985.     

1H NMR assignments for t-2-deuterio-r-1-methyl-1-phenylcyclopropane and c-2-deuterio-r-1-methyl-1-phenylcylclopropane. A literature correction

The synthesis and ¹H NMR spectra of the cis and trans monodeuterated isomers of 2-deuterio-1-methyl-1-phenylcyclopropane have been previously reported. We have prepared one of the isomers, c-2-deuterio-r-1-methyl-1-phenylcyclopropane, by a different, stereospecific, route. We now wish to correct the original ¹H NMR assignments which were in error.     

Cyclization reactions 31. Synthesis of 2-methyl-2-halomethylbenzimidazo [2,1-b]thiazolidinium salts and their conversions to N-(2-methyl-2,3-epithio-propyl)benzothiazol-2-ones

In a novel synthesis, from 2-methyl-2-halomethylbenzimidazo[2,1-b]thiazolidinium salts, by means of their recyclization under the influence of alkali, N-(2-methyl-2, 3-epithiopropyl)benzimidazol-2-ones have been obtained. Syntheses of the indicated salts from N-methallylbenzimidazole-2-thiones are described.Institute of Physical Organic Chemistry and Coal-Tar Chemistry, Academy of Sciences of the Ukraine, Donetsk 3400114. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 706–710, May, 1994. Original article submitted May 4, 1994.     

Synthesis of alkylphenanthrenes from naphthylalkylidenemalonodinitriles. A route to 1-methyl-, 2-methyl-, and 1,2-dimethylphenanthrene

The study has been carried out to evaluate the feasibility of synthesis of 1-methyl-, 2-methyl-, 1,2-dimethyl-, and 1-ethyl-2-methylphenanthrene through the annulation of the naphthalene system with the exploitation of the dicyanovinyl moiety of 2-naphthylalkylidenemalonodinitriles as an active electrophile in cold solutions of concentrated sulfuric acid. 2-(2-Naphthyl)propanal (3), 1-(2-naphthyl)propan-2-one (9), 3-(2-naphthyl)butan-2-one (14), and 3-(2-naphthyl)pentan-2-one (19) had been condensed with malonodinitrile to afford 2-naphthylalkylidenemalonodinitriles which were then cyclised to give 4-amino-1-methylphenanthrene-3-carbonitrile (5), 4-amino-2-methylphenanthrene-3-carbonitrile (11), 4-amino-1,2-dimethylphenanthrene-3-carbonitrile (16), and 4-amino-1-ethyl-2-metylphenanthrene-3-carbonitrile (21). The nitrile function has been removed from the aminonitriles, with the exception of 21, through hydrolysis and decarboxylation in alkaline ethanolic solutions under elevated pressure (∼3 MPa) and temperature 220-230°C to give the respective 4-amino-methylphenanthrenes. Diazotisation of the phenanthreneamines and the reaction with hypophosphorus acid has lead to the methylphenanthrenes in moderate yields (50-52%).     

New synthesis of octahydro-2-methyl-2H-pyrazino[1,2-a]pyrazine

A new method has been developed for the synthesis of octahydro-2-methyl-2H-pyrazino-[1,2-a]pyrazine. 2-Benzylaminoethanol was the starting material.     

4-Hydroxy-2-quinolones. 90. Synthesis and antitubercular activity of 4-methyl-2-thiazolylamides of halo-substituted 4-hydroxy-2-oxo-1,2-dihydro-3-quinolinecarboxylic acids

Several variants were studied for the synthesis of esters of halogen derivatives of 4-hydroxy-2-oxo-1,2-dihydro-3-quinolinecarboxylic acids, whose reaction with 2-amino-4-methylthiazole gives the corresponding hetarylamides. Results are given for a study of the antitubercular activity of these products. Communication 89, see ref. [1]. __________ Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 71–76, January, 2006.     

Spiropyrans and spirooxazines

The Duff formylation of 5-bromo- or 5-chloro-8-hydroxyquinoline leads to the corresponding 7-formyl derivatives, condensation of which with 2-methyleneindolines or 3H-indolium halides in the presence of a base afforded new photochromic 6′-halo-substituted spiro[indoline-2,2′-2H- pyrano[3,2-h]quinolines]. Thermal and photo-induced isomerization of compounds obtained have been investigated by 1H NMR and UV spectroscopy.     

Synthesis and some reactions of perfluoro-2-methyl-2,4-pentadiene

Conclusions A new method was found for the synthesis of perfluoro-2-methyl-2,4-pentadiene. It was established that the latter adds MeOH in the 1,4 position, and is isomerized by SbF₅ to tris(trifluoromethy1)fluoroallene.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1920–1922, August, 1981.The authors express their gratitude to A. P. Kurbakova and L. A. Leites for taking and interpreting the Raman spectra.     

Synthesis of N-substituted 3-hydroxy-2-methyl-4-pyridones and -pyridonimines

Carbohydrates with 1,4 glycosidic bonds like maltose, lactose, dextrin or starch react with primary amines as well as amino acids or proteins to give i.e. 3-hydroxy-2-methyl-4-pyridones 5 and 3-hydroxy-2-methyl-4-pyridonimines 7. A generally applicable synthesis of compounds of this type is described. The pyridones 5 and pyridonimines 7 are strongly complexing agents. Molybdenum-derivatives, for instance, are suitable as fairly stable oxidation catalysts.     

New synthesis of secondary carboxamide by using 2-methyl-2-oxazoline as a building block

New method for the synthesis of secondary carboxamides of type, R²NHCOR¹, which utilizes 2-methyl-2-oxazoline as a carboxamide building block and various halides, R²X, has been developed.     

An easy access to 7-methyl-2-naphthalenecarbonitrile

A practical and cost-effective procedure has been developed for the synthesis of 7-methyl-2-naphthalenecarbonitrile, the precursor of the anticoagulant agents YM-60828 or YM-96765. This new route generates the key intermediate in only two steps from readily available 3-cyanopropionaldehyde dimethyl acetal and m-tolualdehyde, without requiring chromatographic purification. The synthesis involves condensation of the cyano derivative with the aldehyde and subsequent cyclodehydration.     

A convenient synthesis of 3,4-dihydro-2-methyl-3-oxo-2H-1,4-benzoxazine-2-carboxylic acids and 3,4-dihydro-2-methyl-3-oxo-2H-pyrido[3,2-b]-1, 4-oxazine-2-carboxylic acid

A convenient one pot synthesis of ethyl 3,4-dihydro-2-methyl-3-oxo-2H-1,4-benzoxazine-2-carboxylates and 3,4-dihydro-2-methyl-3-oxo-2H-pyrido[3,2-b]-1,4-oxazine-2-carboxylates and their conversion into the respective carboxylic acids are described.     

Enzymatic desymmetrization of 2-amino-2-methyl-1,3-propanediol: asymmetric synthesis of (S)-N-Boc-N,O-isopropylidene-α-methylserinal and (4R)-methyl-4-[2-(thiophen-2-yl)ethyl]oxazolidin-2-one

We report herein, the novel enzymatic desymmetrization of 2-tert-butoxycarbonylamino-2-methyl-1,3-propanediol 1. This method makes it possible to prepare (S)-N-Boc-N,O-isopropylidene-α-methylserinal 3, which is a chiral building block for the synthesis of a variety of α-substituted alanine derivatives. Moreover, optically active (4R)-methyl-4-[2-(thiophen-2-yl)ethyl]oxazolidin-2-one 4, one of the key intermediates in the synthesis of a novel immunosuppressant, has been prepared by this methodology.