XDOTs, EDXTs, EDOXs, and 2(5)-X(2)-EDOTs: Ring Size Variations, Heteroanalogs, and Derivatives of EDOT with Substituents at the Thiophene Ring

PEDOT ◽  
2010 ◽  
pp. 315-350
Keyword(s):  
Thiophene Ring ◽  
Ring Size ◽  
Derivatives Of

scholarly journals The Fluoride Anion-Catalyzed Sulfurization of Thioketones with Elemental Sulfur Leading to Sulfur-Rich Heterocycles: First Sulfurization of Thiochalcones

Molecules ◽  
2021 ◽  
Vol 26 (4) ◽  
pp. 822
Author(s):  
Grzegorz Mlostoń ◽  
Jakub Wręczycki ◽  
Katarzyna Urbaniak ◽  
Dariusz M. Bieliński ◽  
Heinz Heimgartner
Keyword(s):  
Elemental Sulfur ◽  
Fluoride Anion ◽  
Ring Size ◽  
Mild Conditions ◽  
Tetrabutylammonium Fluoride ◽  
Cesium Fluoride ◽  
Secondary Reactions ◽  
Derivatives Of

Fluoride anion was demonstrated as a superior activator of elemental sulfur (S8) to perform sulfurization of thioketones leading to diverse sulfur-rich heterocycles. Due to solubility problems, reactions must be carried out either in THF using tetrabutylammonium fluoride (TBAF) or in DMF using cesium fluoride (CsF), respectively. The reactive sulfurizing reagents are in situ generated, nucleophilic fluoropolysulfide anions FS(8−x)−, which react with the C=S bond according to the carbophilic addition mode. Dithiiranes formed thereby, existing in an equilibrium with the ring-opened form (diradicals/zwitterions) are key-intermediates, which undergo either a step-wise dimerization to afford 1,2,4,5-tetrathianes or an intramolecular insertion, leading in the case of thioxo derivatives of 2,2,4,4-tetramethylcyclobutane-1,3-dione to ring enlarged products. In reactions catalyzed by TBAF, water bounded to fluoride anion via H-bridges and forming thereby its stable hydrates is involved in secondary reactions leading, e.g., in the case of 2,2,4,4-tetramethyl-3-thioxocyclobutanone to the formation of some unexpected products such as the ring enlarged dithiolactone and ring-opened dithiocarboxylate. In contrast to thioketones, the fluoride anion catalyzed sulfurization of their α,β-unsaturated analogues, i.e., thiochalcones is slow and inefficient. However, an alternative protocol with triphenylphosphine (PPh3) applied as a catalyst, offers an attractive approach to the synthesis of 3H-1,2-dithioles via 1,5-dipolar electrocyclization of the in situ-generated α,β-unsaturated thiocabonyl S-sulfides. All reactions occur under mild conditions and can be considered as attractive methods for the preparation of sulfur rich heterocycles with diverse ring-size.

Strukturvergleich bei 9,10-Dihydro-9,10-anthrylen-Verbindungen des Magnesiums und des Alkylaluminiums / Comparison between the Structures of 9,10-Dihydro-9,10-anthrylene Compounds of Magnesium and Alkylaluminium

1985 ◽  
Vol 40 (11) ◽  
pp. 1504-1510 ◽  
Author(s):  
Herbert Lehmkuhl ◽  
Abdul Shakoor ◽  
Klaus Mehler ◽  
Carl Krüger ◽  
Yi-Hung Tsay
Keyword(s):  
Ring Size ◽  
Coordination Geometry ◽  
Chemical Behaviour ◽  
Trimethylsilyl Derivatives ◽  
Derivatives Of

In magnesium as well as in aluminium derivatives of anthracene (1−4, 8) and its trimethylsilyl derivatives (5, 6 and 11), the metals occupy the axial positions at C9 and CIO, to form five-, seven- or ten-membered metallacycles, respectively, in 1−3, 5, 6 and 11. It appears that the metalla-ring size, and thus the coordination geometry of the bridging metal is of influence upon the chemical behaviour.

The formation and reactions of carbanionic derivatives of methyl phosphazenes

1981 ◽  
Vol 59 (17) ◽  
pp. 2654-2664 ◽  
Author(s):  
Keith D. Gallicano ◽  
Richard T. Oakley ◽  
Norman L. Paddock ◽  
Rajendra D. Sharma
Keyword(s):  
Oxidative Coupling ◽  
Electrostatic Interactions ◽  
Ring Size ◽  
Cyclic Phosphazenes ◽  
Derivatives Of

The cyclic phosphazenes N3P3Ph4Me2, N3P3Me6, and N4P4Me8 are deprotonated by alkyllithiums. The resulting carbanions react with monofunctional electrophiles to form phosphazenes carrying the groups PCH2R (R = Me, Br, I, PhC(O), COOH AsMe2, Me3M (M = Si, Ge, Sn)). Two phosphazenyl groups can be joined either by the use of a difunctional halide or by oxidative coupling of organo-copper derivatives. The formation of the carbanions, the extent of deprotonation, substituent orientation, and the dependence of reactivity on ring size, are interpreted in terms of a balance between π-electron energies and electrostatic interactions.

Vitamin D relatives. Part I. B-thiophene-des-A-cholestanes. Solvolytic reactions of some derivatives of 2,2-disubstituted cyclohexane-1,4-diol and 4-hydroxycyclohexan-1-one

1986 ◽  
Vol 64 (8) ◽  
pp. 1536-1539 ◽  
Author(s):  
Jacek W. Morzycki
Keyword(s):  
Vitamin D ◽  
Thiophene Ring ◽  
Derivatives Of

Some derivatives of des-A-cholestane with a thiophene ring B have been prepared from triketone 2. The reactions of tosylates of C-10 alcohols (7b, 9b, and 8c) leading to A-ring ethers (10 and 11) and olefin 5, respectively, have been studied. The solvolysis of tosylate 4c and the Bamford–Stevens reactions of p-tosylhydrazones 3c and 13b are also discussed.

The effect of ring size in N-benzoyl saturated heterocyclic amides

1981 ◽  
Vol 34 (11) ◽  
pp. 2307 ◽  
Author(s):  
CW Fong ◽  
HG Grant
Keyword(s):  
Crystal Structure ◽  
Ring Size ◽  
Intramolecular Exchange ◽  
Derivatives Of ◽  
Exchange Data

The structures of the N-benzoyl derivatives of aziridine, azetidine, pyrrolidine, piperidine, hexamethyleneimine and heptamethyleneimine in solution have been investigated by 13C n.m.r. spectroscopy. In conjunction with literature crystal structure and dynamic intramolecular exchange data, it has been concluded that N-benzoylaziridine and N-benzoylazetidine possess pyrimidal nitrogen atoms in solution. The N-benzoyl derivatives of pyrrolidine, �piperidine, hexamethyleneimine and heptamethyleneimine have planar or near planar nitrogen atoms.

Partition coefficients and ultraviolet absorption maxima for the cinnamoyl derivatives of some long-chain and large-ring amines

1970 ◽  
Vol 48 (8) ◽  
pp. 1340-1343 ◽  
Author(s):  
D. J. Currie ◽  
H. L. Holmes
Keyword(s):  
Nitrogen Atom ◽  
Chain Length ◽  
Partition Coefficients ◽  
The Other ◽  
Ring Size ◽  
Amide Nitrogen ◽  
Derivatives Of ◽  
Limiting Value ◽  
Long Chain ◽  
Amide Nitrogen Atom

Partition coefficients of the title compounds in the system cyclohexane–water do not increase steadily with increasing chain length or ring size but level off to a limiting value. Reasons are advanced to account for this observation. Absorption maxima, on the other hand, are not influenced by the size of the ring or the length of the chain but are dependent only upon the degree of substitution on the amide nitrogen atom.

scholarly journals In VirtoAntioxidant Activities of New 4,5-Dihydro-1H,2,4-triazol-5-ones having Thiophene Ring with their Acidic Properties

2011 ◽  
Vol 8 (4) ◽  
pp. 1734-1746 ◽  
Author(s):  
H. Yuksek ◽  
F. Islamoglu ◽  
O. Gursoy Kol ◽  
S. Bahceci ◽  
M. Bekar ◽  
...  
Keyword(s):  
Isopropyl Alcohol ◽  
Antioxidant Activities ◽  
Thiophene Ring ◽  
Butyl Alcohol ◽  
Dimethyl Formamide ◽  
Acidic Properties ◽  
Alkyl Aryl ◽  
Neutralization Potential ◽  
New Compounds ◽  
Derivatives Of

Seven new 3-alkyl(aryl)-4-(2-thienymethylenamino)-4,5-dihydro-1H-1,2,4-triazol-5-ones(2)were synthesized by the reactions of 3-alkyl(aryl)-4-amino-4,5-dihydro-1H-1,2,4-triazol-5-ones(1)with thiophene-2-carbaldehyde. In addition,N-acetyl derivatives of compounds2d-2gwere also prepared. The structures of eleven new compounds synthesized were determined by elemental analysis as well as IR, NMR and UV spectral data. In addition, compounds2a-gand3a,3b,3d-fwere also screened for their antioxidant activities and2a-gwere potentiometrically titrated with tetrabutylammonium hydroxide (TBAH) in four nonaqueous solvents (isopropyl alcohol,t-butyl alcohol, acetonitrile andN,N-dimethyl formamide). Also half-neutralization potential values and the corresponding pKa values were determined in all cases.

Influence of Ring Size in Conformationally Restricted Ring I Analogs of Paromomycin on Antiribosomal and Antibacterial Activity

2021 ◽  
Author(s):  
Michael Pirrone ◽  
Sven N. Hobbie ◽  
Andrea Vasella ◽  
Erik Bottger ◽  
Crich David
Keyword(s):  
Antibacterial Activity ◽  
Aminoglycoside Antibiotic ◽  
Side Chain ◽  
Ring Size ◽  
Conformationally Restricted ◽  
Derivatives Of

In order to further investigate the importance of the conformation of the ring I side chain in aminoglycoside antibiotic binding to the ribosomal target several derivatives of paromomycin were designed...

scholarly journals A simple and easy to perform synthetic route to functionalized thienyl bicyclo[3.2.1]octadienes

2020 ◽  
Vol 16 ◽  
pp. 1092-1099
Author(s):  
Dragana Vuk ◽  
Irena Škorić ◽  
Valentina Milašinović ◽  
Krešimir Molčanov ◽  
Željko Marinić
Keyword(s):  
Aldol Condensation ◽  
Thiophene Ring ◽  
Aldol Reaction ◽  
Synthetic Route ◽  
Condensation Reactions ◽  
Thiophene Derivatives ◽  
Wittig Reactions ◽  
Aldol Condensation Reactions ◽  
Derivatives Of

In order to prepare novel polycyclic derivatives of bicyclo[3.2.1]octadiene systems fused with a thiophene ring, photochemical cyclization and aldol condensation reactions were carried out. The starting substrates were easily obtained by a Vilsmeier–Haack reaction of bicyclo[3.2.1]octadiene thiophene derivatives with dimethylformamide. From the obtained carbaldehydes, novel methyl, methoxy, and cyano-substituted styryl thienobenzobicyclo[3.2.1]octadiene derivatives were synthesized through Wittig reactions and subjected to photochemical cyclization, in terms of obtaining the new annulated structures. As part of this study, the aldol reaction of the starting 2-substituted carbaldehyde with acetone was also performed, which produced the thieno-fused benzobicyclo[3.2.1]octadiene compound with an extended conjugation.

Sign in / Sign up

Export Citation Format

Share Document