α,β-Epoxyketon → Alkinon-Fragmentierung II: Pyrolytischer Zerfall der Hydrazone aus α,β-Epoxyketonen und N-Amino-aziridinen. Über synthetische Methoden, 4. Mitteilung

Numerous examples illustrate the course of the thermolysis of hydrazones derived from α,β-epoxyketones and 2-phenyl- or trans-2,3-diphenyl-1-amino-aziridines. This process constitutes a preparatively useful method for the fragmentation of α,β-epoxyketones to acetylenic carbonyl compounds including acetylenic aldehydes. Monohydrazones from phenylglyoxal and substituted N-amino-aziridines decompose smoothly and stereospecifically to the corresponding olefins and diazoacetophenone; such a process might also be useful for the preparation of other α-diazocarbonyl compounds.     

The investigation in 2,3'-biquinoline series 26.* Regioselective nitration of 1'-alkyl-1',4'-dihydro-2,3'-biquinolin-4'-ones and 1'-alkyl-1',2'-dihydro-2,3'-biquinolin-2'-ones

The nitration of 1'-alkyl-1',4'-dihydro-2,3'-biquinolin-4'-ones and 1'-alkyl-1',2'-dihydro-2,3'-biquinolin-2'-ones has been investigated. It was shown that the regioselectivity of nitration of the first depends on the acidity of the medium and the order of adding reactants. In strongly acidic medium 1'-alkyl-5,6'-dinitro-1',4'-dihydro-2,3'-biquinolin-4'-ones or mixtures of them with 1'-alkyl-5-nitro-1',4'-dihydro-2,3'-biquinolin-4'-ones are formed. In less acidic media 1'-alkyl-6'-nitro-1',4'-dihydro-2,3'-biquinolin-4'-ones and then 1'-alkyl-6,6'-dinitro-1',4'-dihydro-2,3'-biquinolin-4'-ones are formed. Nitration of 1'-alkyl-1',2'-dihydro-2,3'-biquinolin-2'-ones leads to 1'-alkyl-6'-nitro-1',2'-dihydro-2,3'-biquinolin-2'-one and then 1'-alkyl-6,6',8'-trinitro-1',2'-dihydro-2,3'-biquinolin-2'-one. *For Communication 25 see [1]. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 578-585, April, 2009.     

Investigations in the Field of 2,3'-Biquinolyl. 14. Reaction of Dihydro Derivatives of 2,3'-Biquinolyl with Bromine and Iodine

Methods were developed for the synthesis of 6'-bromo- and 6',8'-dibromo-2,3'-biquinolyls and 3',4'-dibromo- and 3',4',6'-tribromo-1'-ethoxycarbonyl-1',2',3',4'-tetrahydro-2,3'-biquinolyls on the basis of the bromination of the dihydro derivatives of 2,3'-biquinolyl. It was shown that the reaction of 1'-alkyl-1',4'-dihydro-2,3'-biquinolyls with bromine and iodine leads to 1'-alkyl-1',2'-dihydro-2,3'-biquinolyl-2'-ones.     

Réactivité de l'hypochlorite de tertiobutyle dans l'oxydation du benzothiophene

In reaction with benzothiophene, t-butyl hypochlorite acts as an oxidizing reagent and a chlorination reagent. A mixture of 3-ehlorobenzothiophene, three 2,3-dichloro-2,3-dihydrobenzothio-phene 1-oxide isomers (trans-anti: trans-syn; cis-anti) and 2-chlorobenzothiophene 1-oxide was obtained. With a large exces of t-butyl hypochlorite, the reaction leads to 2,3-dichlorobenzothio-phene, 2,3-dichlorobenzothiophene 1-oxide. 2,2,3-trichloro-2,3-(lihydrobenzothiophene 1-oxide and 2,3-dichloro-3-oxobenzothio-phene 1-oxide. In any case, oxidation stops at the level of the sulfoxide.     

羟基功能化离子液体与溶菌酶相互作用的研究

采用荧光光谱和紫外吸收光谱研究了羟基功能化离子液体1-(1,2-二羟基丙基)-3-甲基咪唑氯盐([2,3-dhpmim]Cl)、1-(1,2-二羟基丙基)-3-甲基咪唑四氟硼酸盐([2,3-dhpmim]BF4)、1-(1,2-二羟基丙基)-3-甲基咪唑六氟磷酸盐([2,3-dhpmim]PF6)与溶菌酶的相互作用。研究发现此3种离子液体对溶菌酶的荧光猝灭均为静态猝灭;同步荧光显示离子液体与溶菌酶肽链上的色氨酸残基作用,色氨酸残基微环境发生改变;结合常数和结合位点数按照[2,3-dhpmim]Cl、[2,3-dhpmim]BF4、[2,3-dhpmim]PF6顺序依次增大,并随温度的升高而增大。     

Dioxodihydrobenzo[b]furoindoles

The synthesis and some properties of the isomeric 2,3-dioxo-2,3-dihydro-1H-benzo[b]furo[2,3-g]- and 2,3-dioxo-2,3-dihydro-1H-benzo[b]furo[3,2-g]indoles are described. Georgian Technical University, Tbilisi 380075. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, 627–630, May, 1999.     

The mass spectral fragmentation of 1a,3-disubstituted 4-benzoyl-1a,2,3,4- tetrahydrooxazirino

The mass spectrometric behaviour of four 1a,3-disubstituted 4-benzoyl-1a,2,3,4-tetrahydrooxazirino[2,3-a][1,5]benzodiazepines has been studied with the aid of mass-analyzed ion kinetic energy spectrometry and accurate mass measurements under electron impact ionization. All compounds show a tendency to eliminate a neutral oxygen atom, or oxygen atom plus benzoyl or aryl radicals, or oxygen atom plus CO molecule to yield 2,3-dihydro-1H-1,5-benzodiazepine derivative ions, or 1-benzoyl-2,3-dihydro-1H-1,5-benzodiazepine ions, which could further lose benzoyl to give 2,3-dihydro-1H-1,5-benzodiazepine ions. All compounds also show a tendency to eliminate a benzoyl radical to produce 1a,2,3,4-tetrahydrooxazirino[2,3-a][1,5]benzodiazepine ions. Both oxazirino[2,3-a][1,5]benzodiazepine ions and 2,3-dihydro-1H-1,5-benzodiazepine ions can undergo diazepine ring contraction rearrangement to yield benzimidazole ions by loss of propene or styrenes and other small fragments. The oxazirino[2,3-a][1,5]benzodiazepine ions [M(+)-PhCO] also undergo rearrangement reactions to form benzoxazole ions and benzimidazole ions. Copyright 1999 John Wiley & Sons, Ltd.     

Synthesis of 2,3-dioxo-2,3-dihydro-4-methyl-6-chloro-1H-pyrrolo[2,3-b]pyridine and its 1-α-L-arabinopyranoside

A new type of isatin analog-2,3-dioxo-2,3-dihydro-4-methyl-6-chloro-1H-pyrrolo[2,3-b]pyridine — was obtained by oxidation of 4-methyl-6-chloro-1H-pyrrolo(2,3-b]pyridine. Condensation of L-arabinose with 4-methyl-6-chloro-2,3-dihydropyrrolo[2,3-b]pyridine and subsequent acetylation and dehydrogenation gave 1-(2,3,4-tri-O-acetyl--L-arabinopyranosyl)-4-methyl-6-chloropyrrolo[2,3-b]pyridine, which served as the starting compound for the synthesis of 1--L-arabinopyranosyl-4-methyl-6-chloropyrrolo[2,3-b]pyridine. Oxidation of 1-(2,3,4-tri-O-acetyl-L-arabinopyranosyl)-4-methyl-6-chloropyrrolo[2,3-b]pyridine gave 1-(2,3.4-tri-O-acetyl--L-arabinopyranosyl)-2,3-dioxo-2,3-dihydro-4-methyl-6-chloropyrrolo [2,3-b]pyridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1083–1086, August, 1977.     

Investigation of 2,3'-Biquinolyl. 10. The Regioselectivity of the Reaction of 2,3'-Biquinolyl and 1'-Alkyl-3-(2-quinolyl)quinolinium Halides with Halo Derivatives in the Presence of Metallic Lithium and Magnesium

2,3'-Biquinolyl reacts with halo derivatives in the presence of metallic lithium to give addition products at position 4', treatment of which with water gives 4'-R-1',4'-dihydro-2,3'-biquinolyls and with halo derivatives gives 1'-alkyl-4'-R-1',4'-dihydro-2,3'-biquinolyls. The reaction of 2,3'-biquinolyl with halo derivatives in the presence of metallic magnesium gives a mixture of products of addition at positions 2' and 4'. 1-Alkyl-3-(2-quinolyl)quinolinium halides and halo derivatives with metallic magnesium give 1'-alkyl-2'-R-1',2'-dihydro-2,3'-biquinolyls but form a complex mixture of substances when metallic lithium is used.     

二芳杂环基乙烯的合成及其光致变色反应研究

本文报道了2,3-双 (1,2-二甲基-3-吲哚基)-2-丁烯 (DF1),2,3-双 (1,4-二苯基-2-甲基-3-吡咯基)-2-丁烯 (DF2), 2,3-双(1-对甲苯基-4-苯基-2-甲基-3-吡咯基)-2-丁烯 (DF3), 2,3-双(1-对溴苯基-4-苯基-2-甲基-3-吡咯基)-2-丁烯 (DF4) 和2,3-双 (1-对甲氧苯基-5-苯基-2-甲基-3-吡咯基)-2-丁烯 (DF5) 的合成,以及它们的光致变色行为的研究。特别是DF1和DF5的光呈色和光消色过程进行了较为细致的研究。     

Reaction of 2,3-Dihydro-1,5-benzothiazepines and Phenylacetyl Chloride in the Presence of Triethylamine： A New Aspect on the Formation Mechanism of Dihydro-1,3-oxazin-4-one Derivatives

2a,4-Disubstituted 2,2a,3,4-tetrahydro-2-phenyl-1H-azeto[2,1-d][ 1,5]benzothiazepin-1-ones, as well as 2-substi-tuted 2,3-dihydro-3-phenylacetyl-2-styryl-benzothiazoles and 4a,6-disubstituted 3- .benzyl-4a,5-d/hydro-2-phenyl-1H,6H-[1,3]oxazino[2,3-d][1,5]benzothiazepin-1-ones, were obtained from the reaction of 2,4-disubstituted 2,3-dihydro-1,5-benzothiazepines with phenylacetyl chloride in the presence of triethylamine. The mechanism for the formation of 4a,5-dihydro-1H,6H-[1,3]oxazino[2,3-d][1,5]benzothiazepin-1-ones, 2,3-dihydro-1,3-oxazin-4-one derivatives, was suggested.     

Reactivity of [1(2,3)4]pentamantane (Td-pentamantane): a nanoscale model of diamond

To model the chemical properties of the hydrogen-terminated nanodiamond {111} and {110} surfaces, the functionalizations of the higher diamondoid [1(2,3)4]pentamantane were studied. [1(2,3)4]Pentamantane reacts selectively with neat bromine to give the medial 2-mono- and 2,4-disubstitution products. In contrast, oxidation with nitric acid as well as single-electron-transfer oxidation involving the [1(2,3)4]pentamantane radical cation results in apical C7-substitutions. This substitution pattern dominates in the free-radical bromination under phase-transfer catalytic conditions that gives a mixture of 7- and 2-bromo[1(2,3)4]pentamantane in a 95:5 ratio. Replacement of the functional groups in [1(2,3)4]pentamantane occurs without isomerization. This was demonstrated for the interconversions of the bromo and hydroxy derivatives as well as for the preparation of [1(2,3)4]pentamantyl-7-thiol from 7-hydroxy[1(2,3)4]pentamantane. Thus, the selective functionalization of hydrogen-terminated nanodiamonds is possible by means of reactions with common electrophiles-oxidizers.     

Isomeric Dioxodihydro-1H-Benzo[b]thiophenoindole Synthesis and Properties

The synthesis and properties of new heterocyclic systems are described: isomeric 2,3-dioxo-2,3-dihydro-1H-benzo[b]thiopheno[2,3-g]-, 1,2-dioxo-1,2-dihydro-1H-benzo[b]thiopheno[3,2-e]-, and 2,3-dioxo-2,3-dihydro-1H-benzo[b]thiopheno[2,3-f]indoles. The reduction of the latter to the corresponding unsubstituted benzo[b]thiophenoindoles depends on both the nature of the reducing agent and the reaction conditions.     

Synthesis of 2,3-tetramethylene-5-arenesulfonamidobenzofurans

The reaction of N-arenesulfonyl-1,4-benzoquinonimines with 1-morpholino(piperidino)-1-cyclohexene gives 2,3-dihydro-2-morpholino(piperidino)-2,3-tetramethylene-5-arene-sulfonamidobenzofurans. Refluxing of the latter in dilute hydrochloric acid gave 2,3-tetramethylene-5-arenesulfonamidobenzofurans, the structure of which was proved by hydrolysis to 2,3-tetramethylene-5-aminobenzofuran and conversion of it to the previously described 2,3-tetramethylene-5-hydroxybenzofuran.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 872–874, July, 1972.     

Efficient preparation of highly optically active (S)-(-)-2,3-allenols and (R)-(+)-2,3-allenyl acetates by a clean novozym-435-catalyzed enzymatic separation of racemic 2,3-allenols

Novozym-435 has been found to be an effective biocatalyst for the kinetic resolution of a series of racemic 2,3-allenols, affording highly optically active (S)-(-)-2,3-allenols and (R)-(+)-2,3-allenyl acetates in high yields and with excellent ee values. The reaction of 3-(n-butyl)-3,4-pentadien-2-ol (1 a) was successfully performed on a 10 g scale to afford the corresponding (S)-(-)-2,3-allenol (1 a) and (R)-(+)-2,3-allenyl acetate (2 a) in synthetically useful amounts and with high ee values. The advantages of this reaction are the ready availability of the starting materials, high stereoselectivities for both (-)-2,3-allenols and (+)-2,3-allenyl acetates, the use of a relatively high substrate concentration, and a lower catalyst loading. The resulting (S)-(-)-2,3-allenol 1 a can be converted into the corresponding chiral 2,5-dihydrofuran and the vinylic epoxide.     

Structural Determination of the [4+2] Dimer of 2,3-Dimethylene-2,3-Dihydrothiophene from Deuterium Labeling Study

2,3-Dimethylene-2,3-dihydrothiophene (1a), prepared by the flash vacuum pyrolysis of 3-methyl-2-thienylmethyl benzoate (7a), rapidly dimerizes to form a [4 + 2] dimer 6. The structure of the [4+2] dimer 6 was confirmed by comparing its NMR spectrum with that of the [4 + 2] dimers from 2-dideuteriomethylene-3-methylene-2,3-dihydrothiophene (1b) and 2-methylene-3-dideuteriomethylene-2,3-dihydrothiophene (1c).     

Site-selective Suzuki-Miyaura reactions of 2,3-dibromo-1H-inden-1-one

The first transition metal-catalyzed cross-coupling reactions of 2,3-dibromo-1H-inden-1-one are reported. The Suzuki-Miyaura reaction of 2,3-dibromo-1H-inden-1-one with 2 equiv of arylboronic acid gave 2,3-diaryl-1H-inden-1-ones. The reaction with 1 equiv of arylboronic acid gave 2-bromo-3-aryl-1H-inden-1-ones with very good site-selectivity. The one-pot reaction of 2,3-dibromo-1H-inden-1-one with two different arylboronic acids afforded 2,3-diaryl-1H-inden-1-ones containing two different terminal aryl groups.     

Azaindolines: derisking the indoline structural alert

4-Substitued azaindolines, which are isosteres of indolines, are useful synthetic building blocks that reduce the risk of bioactivation induced idiosyncratic toxicity have been prepared. Multigram routes to 2,3-dihydro-1H-pyrrolo[2,3-c]pyridine-4-triflate 16, 2,3-dihydro-1H-pyrrolo[2,3-b]pyridine-4-carbonitrile 20 and 4-chloro-2,3-dihydro-1H-pyrrolo[2,3-d]pyridazine 30 are outlined.     

[1] Benzofuro [2,3-d] pyridazines II. Etude des benzofuropyridazones

The synthesis of 1,2-dihydro[1]benzofuro[2,3-d]pyridazin-1-one and 3,4-dihydro [1]benzofuro[2,3-d]pyridazin-4-one was accomplished by the eyclization of appropriately carbonyl-substituted benzofuran derivatives. Another successful synthetic route was provided using 1,2,3,4-tetrahydro[1]benzofuro[2,3-d]pyridazine-1,4 dione and 1,2,3,4-tetrahydro[1]benzofuro[2,3-d]pyridazin-4-one. The structure of a nitrobenzofuropyridazin-4-one was established using nmr and the nuclear Overhauser effect.