The first examples of cycloadditions of 2-diazo-1,3-dicarbonyl compounds to aromatic thioketones

Acyclic 2-diazo-1,3-dicarbonyl compounds react at 20–50 °С with aromatic thioketones and through a cascade process, involving the cycloaddition of a diazo group dipole with the CS bond, elimination of nitrogen from the arising thiadiazoline, and subsequent [1,5]-electrocyclization of the intermediate СS-ylide, the relevant oxathioles being formed in yields of up to 70%. Carbocyclic 2-diazo-1,3-diketones at room temperature react with thiones much more slowly, but with increasing temperature they partly decompose to produce, via Wolff rearrangement, 2-oxoketenes, which yield [4+2]-cycloaddition products, that is oxathiinones and/or oxoketene dimers.     

Bifunctionalized Allenes. Part VIII. An Efficient and Varied Method for the Synthesis of 2-Sulfonylated Alka-2,3-Dienoates

Abstract

An efficient and varied method for the synthesis of 2-sulfonylated alka-2,3-dienoates by intermediate formation of allenecarboxylates, allenyl sulfones, and propargyl sulfinates using the relatively high acidity of the hydrogen atom at the allenic C-1 atom and the [2,3]-sigmatropic rearrangement is described.

Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file.     

Noncovalent linkage of telechelic oligo(dimethylsiloxanes) via end group attachment of host‐cyclodextrins and guest‐adamantanes or guest‐ferrocenes

In this article, we report the noncovalent linkage of terminal substituted oligo(dimethylsiloxanes) bearing cyclodextrins (CD) as host endgroups and adamantan or ferrocene, respectively, as guest endgroups. Structural characterization was performed by ¹H NMR‐, IR‐, and mass spectroscopy. Electron microscopy studies show significant differences in the surface structure of the individual derivatives. In addition, the ferrocene‐terminated di‐and poly(dimethylsiloxanes) are distinguished by a red‐ox activity and reversibility, which also makes the complexes between the ferrocene‐ and CD functionalized siloxanes switchable via electrochemical stimuli. The evidence for a successful complexation of the end groups, and thus the successful supramolecular formation of the siloxane strands, was even performed by shift of the protons in the ¹H NMR spectra. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2472–2482     

Synthesis and reactions of 2,4-disubstituted benzo[b]furano-, benzo[b]thieno- and indolo[3,2-d]-1,3-oxazinium salts

Under acid catalyzed acylation 3-acetamidobenzo[b]furan, -benzo[b]tkiophene, and indole undergo heterocyclization to condensed 1,3-oxazinium salts. Treatment of the salts with ammonium acetate in acetic acid gives the corresponding benzo[b]furano- and benzo[b]thieno[3,2-d]pyrimidines and 2-acetyl-3-acetamidoindole gives pyrimido [5,4-d] indole.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1569–1571, November, 1990.     

Synthesis and reactions of benzo[b]thieno[2,3-c]pyrylium pairs

Benzo[b]thieno[2,3-c]pyrylium perchlorates were obtained in high yields in the acylation of benzo[b]thien-3-ylacetone with aliphatic acid anhydrides in the presence of 70% perchloric acid. Treatment of the products with ammonia converts them to benzo[b]thieno[2,3-c]pyridines (in yields higher than 90%), whereas hydroxy and dialkylamino derivatives of dibenzothiophene were obtained in up to 50% yields by treatment of the products with alkalis or secondary amines, respectively.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1351–1354, October, 1981.     

Dual reactivity of imidic carbonyl ylides in Rh(II)-catalyzed reactions of α-diazocarbonyl compounds with succinimide

Stabilization of imidic carbonyl ylides derived from α-diazocarbonyl compounds and succinimide occurs in two different ways: ylides from diazoesters experience a [1,4]-hydrogen shift to produce the corresponding O-alkylimidates while their analogues with at least one acyl group undergo [1,5]-electrocyclization yielding 1,3-dioxoles.     

Transformations of 4,5,6,7-tetrahydrothieno[3,2-c]-and 1,2,3,4-tetrahydrobenzothieno[2,3-c]pyridines in reactions with alkynes activated by electron-withdrawing substituents

The transformations of tetrahydrothieno[3,2-c]-and tetrahydrobenzothieno[2,3-c]pyridines in the reactions with acetylenedicarboxylic ester, alkyl propiolates, and acetylacetylene in alcohols were studied. Tetrahydrobenzothieno[3,2-d]azocines and 2-methoxyethyl-3-vinyl-aminoethylbenzothiophenes were synthesized. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1003–1009, May, 2007.     

Electrophilic substitution in benzo[b]thieno[2,3-c]pyridines. Nitration

A study was carried out on the nitration of substituted benzo[b]thieno[2,3-c]pyridines. Depending on the conditions, either one nitro group is introduced at C₍₆₎ or two nitro groups are introduced at C₍₆₎ and C₍₈₎. If C₍₆₎ is blocked, a mixture of products is formed.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 706–709, May, 1993.     

A New Set of Gas/Water Partition Coefficients for the Chloromethanes

Summary. In the literature, there is a considerable number of articles and reviews providing data and information on the solubility of chloromethanes in water. However, the substantial difference between the numerical values given by various authors hinders their practical application. In the current work we present the harmonized results of experimentally determined gas/water partition coefficients of CH₂Cl₂, CHCl₃, and CCl₄, in the temperature range from 278 to 343 K, and with on uncertainty limit of less than 10%.     

Electrophilic substitution in benzo[b]thieno- and benzo[b]furo[2,3-c]pyridines. Use of the nuclear overhauser effect for determination of substitution position

The site of electrophilic substitution in benzo[b]thieno- and benzo[b]furo[2,3-c]pyridines has been determined using the nuclear Overhauser effect and by a method based on the difference in reactivity of the isomeric products.L. M. Litvinenko Institute for Physicoorganic Chemistry and Carbon Chemistry. Ukrainian Academy of Sciences, Donetsk 340114. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1199–1202, September, 1997.