Synthesis of 1-functionalized-6-hydroxy-4-methyl and 6,11-dihydroxy-4-methylnaphtho[2,3-g]isoquinoline-5,12-quinones

Using 2-methoxy- and 2,5-dimethoxyacetophenones 8a and 8b as starting materials, 1-chloro-4-methylisoquinoline-5,8-quinone ( 6 ) and its 6-bromo derivative 7 were obtained via multistep sequences. Whereas Diels-Alder condensation of the former compound with homophthalic anhydride ( 22 ) led to a mixture of the two possible isomers: 1-chloro-11-hydroxy-4-methylnaphtho[2,3-g]isoquinoline-5,12-quinone ( 23 ) and 1-chloro-6-hydroxy-4-methylnaphtho[2,3-g]isoquinoline-5,12-quinone ( 24 ), this last tetracyclic chloroquinone was specifically obtained from 6-bromo-1-chloro-4-methylisoquinoline-5,8-quinone ( 7 ) and homophthalic anhydride. The 6,11-dihydroxy derivative was then prepared by ammonium nitrate oxidation or photochemically by cycloaddition of benzocyclobutenedione ( 28 ) and 1-chloro-4-methylisoquinoline-5,8-quinone ( 6 ). Chloro compounds were easily substituted by diamines to provide corresponding 1-amino substituted hydroxy tetracyclic quinones.     

Synthesis of 2-substituted methylenecycloalkanes from 1-(dialkyl-borylmethyl)cycloalkenes

Conclusions We have developed a novel general method for the preparation of 2-substituted methylenecycloalkanes, which is based upon the allylboration of carbonyl compounds and alkoxyacetylenes by means of hitherto unknown cycloalkenylmethyl(dialkyl)boranes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, PP. 420–425, February, 1988.     

Synthesis and structural studies of 5,12-dioxocyclams capped by 4-substituted pyridines across the amine nitrogens

A series of 4-substituted pyridine-capped 5,12-dioxocyclams was synthesized and fully characterized. The 4-substituent varied from electron-withdrawing groups (NO2, NO, CN) to electron-donating groups (NHCbz, NH2). The most versatile substituent was the 4-bromo group, which could be replaced by a variety of groups using Stille, Sonogashira, or Buchwald-Hartig palladium-catalyzed chemistry. Copper complexes of a majority of these capped dioxocyclams were synthesized and characterized as well.     

Synthesis of 4-(1-Adamantyl)- and 4-(1-Adamantylmethyl)-substituted Halothiazoles

1-Adamantyl bromomethyl ketone and 1-adamantylmethyl chloromethyl ketone react with potassium thiocyanate in dimethylformamide to give the corresponding thiocyanatoketones which cyclize under the influence of HCl into 4-(1-adamantyl) and 4(-adamantylmethyl)chlorothiazole respectively. 4-(1-Adamantyl)-2-amino-5-bromothiazole and its N-derivative were synthesized by the reaction of 1-adamantyl dibromomethyl ketone with thioureas and N-substituted thiourea in acetonitrile.     

Synthesis of new 1-substituted 4-(2-phenylquinazolin-4-yl)-and 4-(2-phenylquinazolin-4-ylidene) thiosemicarbazides

Two new 1-substituted 4-(2-phenylquinazolin-4-yl)-and 4-(2-phenylquinazolin-4-ylidene) thio-semicarbazides were formed by a multistep domino reaction of imidoyl isothiocyanate derivative with 1,1-di-R-hydrazine in acetone solution. Application of hydrazine hydrate under the same reaction conditions afforded 4-(2-phenylquinazolin-4(3H)-ylidene)-2-(propen-2-yl)-1-(propan-2-ylidene) thio-semicarbazide via a six-step triple-component domino reaction. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1688–1693, November, 2008.     

Synthesis of 4- and 6-substituted nitroindoles

Enolizable ketones react with m-nitroaniline in the presence of strong base such as t-BuOK to give 4- and 6-substituted nitroindoles. The reaction proceeds via oxidative nucleophilic substitution of hydrogen in m-nitroaniline with enolate anions in positions ortho to the amino group giving anionic σ^H adducts that are additionally stabilized by intramolecular interaction between the amino and the carbonyl group. Spontaneous oxidation of the σ^H adducts followed by the Bayer type condensation of the produced ortho-aminonitrobenzyl ketones gives 4- and 6-substituted nitroindoles. The scope of this reaction and its basic mechanistic features are discussed.     

Synthesis of photoactive 1-methyl-1-R-4-(1,4-dioxo-1,4-dihydronaphthalen-2-yl)piperazinium salts

Photoactive 4-(1,4-dioxo-1,4-dihydronaphthalen-2-yl)piperazinium salts were synthesized by alkylation of 3-chloro-2-(piperazin-1-yl)- and 2-arylamino-3-(4-methylpiperazin-1-yl)-1,4-naphthoquinones. Light sensitivities of materials obtained by adsorption of the synthesized piperazinium salts from solution onto oxidized aluminum support were estimated.     

Reduction of 1-substituted anthraquinones to 1- and 4-substituted anthrones

The regioselectivity of reduction of 1-substituted anthraquinones to 1- or 4-substituted anthrones is determined by both the nature of the substituent and the type of the reducing system used. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 2, pp. 355–357, February, 1997.     

5,12-dihydro-6,11-didehydronaphthacene,A derivative of 1,4-didehydronaphthalene

Treatment of the di-lithium derivative of 1,2-diethynyl-benzene ($\text{1}$) with $\text{o}$-xylene-α,α′-diol di-$\text{p}$-toluenesulphonate ($\text{2}$) in tetrahydrofuran led to 5,12-dihydronapthacene ($\text{5}$) as the only identifiable product. This reaction presumably involves 5,12-dihydro-6,11-didehydronaphthacene ($\text{4}$) as an intermediate, and this was confirmed by the formation of 5,12-dihydro-6,11-dideuterio-naphthacene when the reaction was carried out in tetrahydrofuran-$\text{d}$₈.     

Synthesis of 4-substituted 2-azetidinones

4-Substituted 2-azetidinones were obtained in excellent yields from the reaction of various cuprates with 4-acetoxy-2-azetidinone.     

Synthesis of new 2-substituted 6,7-dimethoxy-1-(methylcarbamoyl)-4-spirocyclopentane-1,2,3,4-tetrahydroisoquinolines

New 2-(heterylmethyl) derivatives were synthesized from 6,7-dimethoxy-4-spirocyclopentane-1,2,3,4-tetrahydroisoquinoline-1-carboxylic acid N-methylamide and heterylmethyl chlorides. The reactions of 2-chloroacetyl-substituted tetrahydroisoquinoline with versatile secondary amines and heterylthiols afforded the corresponding 2-aminoacetyl and 2-(heterylsulfanylacetyl) derivatives of tetrahydroisoquinoline series.     

Synthesis and polymerization of 1,5-dioxo-1-methyl-4-azaphosphepane

1,5-Dioxo-1-methyl-4-azaphosphepane was synthesized and polymeized in the presence of water, stannic chloride, or phosphoric acid. Polymers obtained by using these catalysts were shown to have lower molecular weights than nylon 6 samples prepared under identical reaction conditions. Thermal and other physical properties of the phosphorus-containing polyamide are reported and compared with those of nylon 6.     

Synthesis of 6,8-substituted 4-(hydroxyphenylamino)- and 4-(aminophenylamino)-2-methylquinolines

A procedure has been developed for the synthesis of 4-(hydroxyphenylamino)- and 4-(aminophenylamino)-2-methylquinolines having a substituent in the 6(8)-position of the quinoline ring from the corresponding 4-chloro-2-methylquinolines and o-, m-, and p-aminophenols and o-, m-, and p-phenylenediamines.     

The mass spectra of 2- and 4-monohydroxy- and 2, 4-dihydroxy-1, X-naphthyridines

The mass spectra of 2-and 4-monohydroxy-and 2, 4-dihydroxy-1, 5-, -1, 6-, -1, 7-and 1, 8-naphthyridines are reported. Fragmentation mechanisms are proposed and discussed.     

Synthesis of 5-substituted 2-(4- or 3-methoxyphenyl)-4(1H)-quinolones

5-Substituted 7-methoxy-2-(4- or 3-methoxyphenyl)-4(1H)-quinolones 8-17 have been synthesised in good yields from the corresponding 7-methoxy-2-(4- or 3-methoxyphenyl)-5-trifluoromethanesulfonate-4(1H)-quinolones 7 via palladium-mediated cross-coupling reactions or aromatic nucleophilic substitution (SN_Ar) reactions.