Preparation of [5,6]- and [6,6]-oxahomofullerene derivatives and their interconversion by Lewis acid assisted reactions of fullerene mixed peroxides

[60]Fullerene mixed peroxides C60(O)(OOtBu)4 exhibit chemo- and regioselective reactions under mild conditions. The epoxy moiety is opened by ferric chloride to form vicinal hydroxy chloride C60Cl(OH)(OOtBu)4. BF3 is also effective in opening the epoxy moiety. The O-O bond of the fullerene mixed peroxide is cleaved by aluminum chloride to form both [5,6]- and [6,6]-fullerene hemiketals (oxohomo[60]fullerenes). A Hock-type rearrangement is proposed for the formation of the hemiketals, in which a fullerene C-C bond is cleaved. Lewis acids and/or visible light can initiate isomerization of the hemiketal isomers. Single-crystal X-ray analysis and theoretical calculations confirmed the results.     

Revisit to the reaction of [60]fullerene with nitrile ylides generated from imidoyl chlorides and triethylamine

The reaction of [60]fullerene (C₆₀) with nitrile ylides generated from N-benzyl-4-nitrobenzimidoyl chloride/N-(4-chlorobenzyl)-4-nitrobenzimidoyl chloride and triethylamine gave only isomeric monoadducts of C₆₀ with [6,6]-closed structure. No [5,6]-open adduct of C₆₀ could be identified from these reactions. The previously reported [5,6]-open product of C₆₀ should be reassigned as a [6,6]-closed product.     

Synthesis of 3-amino-3,4-dihydroquinazolin-4-one derivatives from anthranilic acid hydrazide and dicarboxylic acids

Treatment of anthranilic acid hydrazide with 2 equiv of ethoxalyl chloride gave the corresponding diester which underwent cyclization in acetic anhydride to produce ethyl 3-(ethoxalylamino)-4-oxo-3,4-dihydroquinazoline-2-carboxylate. Acylation of anthranilic acid hydrazide first with succinic anhydride and then with ethoxalyl chloride led to the formation of 4-[2-(2-{[ethoxy(oxo)acetyl]amino}benzoyl)hydrazino]-4-oxobutanoic acid whose cyclization in acetic acid afforded N-(2-ethoxycarbonyl-4-oxo-3,4-dihydroquinazolin-3-yl)succinamic acid, while in acetic anhydride ethyl 3-(2,5-dioxopyrrolidin-1-yl)-4-oxo-3,4-dihydroquinazoline-2-carboxylate was obtained. The latter was brought into reactions with amines and hydrazine hydrate and alkaline hydrolysis. Acylation of 2-[2-(2-aminobenzoyl)hydrazinocarbonyl]benzoic acid with ethoxalyl chloride gave ethyl N-[2-(phthalimidocarbamoyl)phenyl]oxamate, and with succinic anhydride, 3-[4-oxo-3-phthalimido-3,4-dihydroquinazolin-2-yl]propionic acid. 4-[2-(2-Aminobenzoyl)hydrazino]-4-oxobutanoic acid reacted with phthalic anhydride in boiling acetic acid to give phthalazino[1,2-b]quinazoline-5,8-dione via elimination of succinic acid residue.     

Separation of ternary systems of hydrophilic ionic liquid with miscible organic compounds by RPLC with refractive index detection

A rapid and simple analytical method was developed for the simultaneous and quantitative determination and separation of hydrophilic imidazolium ionic liquids (ILs) (1-butyl-3-methylimidazolium chloride, [C(4)mim]Cl; 1-hexyl-3-methylimidazolium chloride, [C(6)mim]Cl; 1-octyl-3-methylimidazolium chloride, [C(8)mim]Cl; 1-allyl-3-methylimidazolium chloride, [Amim]Cl; or 1-allyl-3-methylimidazolium bromide, [Amim]Br) with miscible ethyl acetate and EtOH and their mixtures using reverse phase liquid chromatography coupled with refractive index detection (RPLC-RI). The influence of 60 to 100% (volume percentage) methanol in the mobile phase on the IL systems ([C(4)mim]Cl, [C(6)mim]Cl, [C(8)mim]Cl, [Amim]Br, or [Amim]Cl)-ethyl acetate-EtOH was investigated. The optimum mobile phase for the system [C(8)mim]Cl-ethyl acetate-EtOH, [C(4)mim]Cl-ethyl acetate-EtOH, [Amim]Br-ethyl acetate-EtOH and [Amim]Cl-ethyl acetate-EtOH was methanol/water (60:40, v/v), and methanol/water (70:30, v/v) for [C(6)mim]Cl-ethyl acetate-EtOH. Under optimum mobile phase conditions for each system, the RSD of the retention time ranged from 0.02 to 0.04%, and the RSDs of the peak area percent ranged from 0.23 to 1.85%, which showed good reproducibility of the RPLC-RI method. The RPLC-RI method can determine IL, ethyl acetate, and EtOH simultaneously in 5 min, and the analytes, especially IL, can be eluted completely. The results show that the RPLC-RI method can be used to separate and determine ILs in mixtures with organic compounds simultaneously and quantitatively.     

Synthesis and reactions of 2,2-[60]fullerenoalkanoyl chlorides

2,2-[60]Fullerenoalkanoyl chlorides (1a-d) were easily and securely prepared from the corresponding 2,2-[60]fullerenoalkanoic acids (2a-d) by the reaction with thionyl chloride in an unusual mixed solvent, CH2Cl2/dioxane. The characterization of 1a-d by 1H and 13C NMR, FT-IR, and MALDI-TOF-MASS was conducted for the first time. The 2,2-[60]fullerenoalkanoyl chlorides thus obtained were readily converted to the corresponding amides and esters in moderate to excellent yields by the condensation with amines and alcohols, respectively. Upon applying the condensation, [60]fullerene-biomolecule hybrids were easily prepared.     

Uncatalyzed reaction of silyl ketene acetals with oxalyl chloride: a straightforward preparation of symmetrical pulvinic acids

[reaction: see text] Several natural pulvinic acids were synthesized. Silyl ketene acetals derived from methyl arylacetates (4 equiv) reacted with oxalyl chloride at -78 degrees C, without the need of adding a catalyst. After treatment of the crude diketones with DBU and acidification with hydrochloric acid, symmetrical pulvinic acids methyl esters were obtained. Saponification of the methyl esters afforded the corresponding pulvinic acids in 60-70% overall yields from oxalyl chloride.     

S-homoadenosyl-L-cysteine and S-homoadenosyl-L-homocysteine. Synthesis and binding studies of hon-hydrolyzed substrate analogues with S-adenosyl-L-homocysteine hydrolase

Treatment of homoadenosine [9-(5-deoxy-beta-D-ribo-hexofuranosyl)adenine] with thionyl chloride and pyridine in acetonitrile gave 6'-chloro-6'-deoxyhomoadenosine, which underwent nucleophilic displacement with L-cysteine or L-homocysteine to give homologated analogues of S-adenosyl-L-homocysteine. Each amino acid in aqueous sodium hydroxide at 60 degrees C gave excellent conversion from the chloronucleoside, and adsorption on Amberlite XAD-4 resin provided more convenient isolation than prior methods. Weak binding of these non-hydrolyzed analogues to S-adenosyl-L-homocysteine hydrolase was observed.     

Cyclization of 3-Cyclopent-2-Enyl-4-Hydroxy[1]Benzopyran-2-One

Cyclization of 3-cyclopent-2-enyl-4-hydroxy[1]benzopyran-2-one (1) with cold cone. sulfuric acid gave a mixture of two products, 2 (10%) and 3 (80%). However, on treatment with mercuric chloride 1 furnished the linear product 4 in 60% yield while with mercuric acetate the bicyclic product 8 was obtained in 50% yield. The structures of products are established by chemical correlation.     

A scalable synthesis of methano[60]fullerene and congeners by the oxidative cyclopropanation reaction of silylmethylfullerene

1,2-Dihydromethano[60]fullerene and its congeners have attracted much interest, but they have been synthesized only in very low yields because of several insurmountable problems. A new three-stage synthesis involving addition of a silylmethylmagnesium chloride to [60]- and [70]fullerene and oxidation of the anionic intermediate with CuCl(2) afforded the methano[60]- and methano[70]fullerenes in 90% and 70% overall yield, respectively. The reaction with 1,4-diorgano[60]fullerene also proceeded smoothly to give a diastereomerically pure 56-π-electron fullerene that has a higher LUMO level than the parent fullerene and gave a higher open-circuit voltage and better power conversion efficiency when fabricated into an organic photovoltaic device.     

Ring-chain isomerism and reactions of 2-(1-anthraquinonecarbonyl)-1,2,3,4-tetrahydrophthalazine

The ring isomer of the corresponding acyl derivative — 5,9-dioxo-17a-hydroxy-9,10,11,16-17,17a-hexahydro-5H-dibenzo[d,e,h]phthalazino[2,3-a]cinnoline — was obtained by acylation of 1,2,3,4-tetrahydrophthalazine with anthraquinone-1-carboxylic acid chloride. Treatment of the product with thionyl chloride or hydrogen chloride gave the deeply colored 5,9-dioxo-9,10,11,16-tetrahydro-5H-dibenzo[d,e,h]phthalazino[2,3-a]cinnolinium chloride. The possibility of charge transfer between the chloride anion and the phthalazinium cation is examined as a reason for the deep coloration. This compound very readily undergoes hydrolytic oxidative cleavage at the C-N bond to give 2-(2-formylbenzyl)-3,7-dioxo-2,3-dihydro-7H-dibenzo[d,e,h]cinnoline.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1411–1415, October, 1977.     

亚甲基[6,6]-富勒(fullerene)[60]单羧酸的合成研究

亚甲基[6,6]-fullerene[60]单羧酸是一个具有化学反应活性的fullerene[60]衍生物,可以作它合成得到一些新的具有潜在生化应用价值的水溶性fullerene[60]衍生物。本文详细报道了常规量合成亚甲基[6,6]-fullerene[60]单羧酸的技术。     

The first synthesis of a methano[60]fullerene with an electron-donating group at the methano-bridge carbon: synthesis and reaction of aminomethano[60]fullerene

[reaction: see text] Aminomethano[60]fullerene was synthesized for the first time as a trifluoromethanesulfonic acid salt by applying the Curtius rearrangement of azidocarbonylmethano[60]fullerene as the key reaction. Aminomethano[60]fullerene thus obtained was found to be able to react with various acyl chlorides to afford the corresponding amides.     

Synthesis of N-alkyl(acyl)-1,2,3,4-tetrahydro-4-methylspiro [quinoline-2-cyclohexanes] and their conversions

The alkylation and acylation of 1,2,3,4-tetrahydro-4-methylspiro[quinoline-2-cyclohexane] and its bromo (methyl) derivatives substituted in the benzene ring, as well as 1,2,3,4-tetrahydro-4-methylspiro[benzo(h)quinoline-2-cyclohexane], were studied. It was established that the N-allyl derivatives ofspiro[tetrahydroquinolinecyclohexanes] are converted to their 8-allyl-substituted analogs by the action of sulfuric acid, boron trifluoride etherate, and aluminum chloride. It was shown that the N-acyl-substituted spiro[tetrahydroquinolinecyclohexanes] are recyclized to spiro[indan-1-cyclohexanes] in phosphoric acid.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 789–796, June, 1993.     

Synthesis of some new spiroindoline derivatives incorporated with pyrazoloheterocycles

Indole-2,3-dione ( 1 ) was treated with malonic acid ( 2 ) in a mixture of ethanol/pyridine to afford 1-[3-(2-oxoindolinylidene)]acetic acid ( 3 ). Compound 3 reacted with thionyl chloride to give the corresponding acid chloride ( 4 ). The acid chloride 4 reacted with arenes in the presence of AlCl₃ to yield 3-(2-oxoindolinylidene)acetophenones 5a–c . Compounds 5a–c reacted with 3-methylpyrazolin-5-one derivatives 6a , b to give 3-aracyl-3-[4′-(3′-methylpyrazolin-5-onyl)]-indoline-2-one derivatives 7a–f . Compounds 7a–f were treated with phosphorus pentoxide in phosphoric acid, with ammonium acetate or methanolic methylamine and with phosphorus pentasulfide to give spiro[indoline-3,4′-(pyrazolo[4,5-b]pyran)]-2-ones 8a–f , spiro[indoline-3,4′-(pyrazolo[4,5-b]-dihydropyridine)]-2-ones 9a–f , 10a–f and spiro[indoline-3,4′-(pyrazolo[4,5-b]thiopyran)]-2-ones 10a–f , respectively. All of the synthesized spiroheterocycle derivatives were identified by conventional spectroscopic methods (IR, ¹H NMR) and elemental analyses. © John Wiley & Sons, Inc.     

Synthesis of [60]fullerene-fused tetrahydronaphthalene and indane derivatives via a pathway switched by aluminum chloride

The addition of aluminum chloride to the manganese acetate-mediated radical reaction of [60]fullerene with 2-arylmalonates, 2-benzylmalonates, and 2-arylcyanoacetates can switch the reaction pathway and affords a variety of structurally novel and scarce [60]fullerene-fused tetrahydronaphthalene and indane derivatives. These products are formed probably through radical addition, followed by Friedel-Crafts-type annulation.     

Novel functionalizations of [60]fullerene-fused lactones

Reactions of [60]fullerene-fused lactones with methylmagnesium bromide and diisobutylaluminum hydride afforded rare fullerene hemiketals and hemiacetals, which were dehydrated by p-toluenesulfonic acid monohydrate or polyphosphonic acid to the corresponding [60]fullerene-fused dihydrofurans. Thus obtained alkyl-substituted and especially unsubstituted [60]fullerene-fused dihydrofurans are difficult to prepare by other methods. The unsubstituted [60]fullerene-fused lactone could react with aliphatic amines to give fullerols.     

Synthesis of 2-dichloromethyl-2-methyl [2-14C]-1,3-dioxolane

The labelled compound was prepared by chlorination of [2-¹⁴C]acetone obtained from the barium salt of [1-¹⁴C]acetic acid by pyrolysis. The reaction product 1,1-dichloro [2-¹⁴C]acetone was converted to 2-dichloromethyl-2-methyl [2-¹⁴C]-1,3-dioxolane by condensation with ethylene glycol in the presence of thionyl chloride. Radiochemical yield: 62% based on [1-¹⁴C]acetic acid.     

Addition von organomagnesium-verbindungen an nicht aktivierte CC-doppelbindungen : IV. Benzylmagnesiumchlorid und olefine

Benzylmagnesium chloride (I) adds to ethylene and 1-alkenes, to the strained CC double bonds in bicyclo[2.2.1]hept-2-ene and bicyclo[2.2.1]heptadiene and to 1,3-alkadienes if the reaction of the etherate of (I) with olefin is carried out in an apolar reaction medium between 60 and 130°. Reaction products of the mono-olefins are the 1,1-adducts; derivatives of divinylcyclohexane are formed with butadiene as 1,3-adducts. With bicyclo[2.2.1]heptadiene the addition of the magnesium compound is followed by an intramolecular MgC-addition to the second double bond forming 2-benzyltricyclo[2.2.1.0¹]hept-3-ylmagnesium chloride.     

N-[3-nitro(amino)coumarin-4-yl]anthranilic acid amides. Synthesis of 6,7,8,13-tetrahydro[1]benzopyrano[4,3-b][1,4] benzodiazepine-6,8-dione

The reaction of 3-nitro-4-chlorocoumarin with anthranilic acid was used to synthesize N-(3-nitro-4-coumarinyl)-anthranilic acid, from which, through the acid chloride, we obtained a number of amides, which were reduced to N-(3-amino-4-coumarinyl)anthranilic acid amides The latter are cyclized under the influence of hydrochloric acid to 6,7,8,13-tetrahydro[1]benzopyrano-[4,3-b][1, 4]benzodiazepine-6,8-dione, which was also obtained from N-(3-amino-4-coumarinyl)anthranilic acid by its thermolysis or treatment with hydrochloric acid.See [1] for our preliminary communication.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1208–1212, September, 1989.     

Furopyridines. I. Synthesis of furo[2,3-c]pyridine

The parent framework of furo[2,3-c]pyridine has been synthesized. 3-Furoic acid chloride ( 2 ) was reduced with bis(triphenylphosphine) copper(1) tetrahydroborate to afford 3-furaldehyde ( 3 ) which was condensed with malonic acid to give β-(3-furyl)acrylic acid ( 4 ). The acrylic acid 4 was converted to the acid azide ( 5 ), which in turn was cyclized to give furo[2,3-c]pyridin-7(6H)-one ( 6 ) by heating at 180° in diphenylmethane. The pyridone 6 was chlorinated with phosphorus oxychloride, followed by reduction with zinc and acetic acid to give furo[2,3-c]pyridine ( 8 ).