- Soluble cycloannulated tetroxa[8]circulane derivatives: Synthesis, optical and electrochemical properties, and generation of their robust cation-radical salts
-
Syntheses of soluble bicycloalkane-annulated tetraoxa[8]circulane derivatives via Lewis acid-catalyzed tetramerization of readily available cycloannulated benzoquinons is described. The ready availability of the soluble circulane derivatives allows the evaluation of their optical and electrochemical properties. These circulanes form stable (isolable) cation-radical salts upon 1-electron oxidation using antimony pentachloride and various aromatic oxidants.
- Rathore, Rajendra,Abdelwahed, Sameh H.
-
p. 5267 - 5270
(2007/10/03)
-
- Cycloadditions of isobenzofuran to a constrained template bearing neighboring dienophiles
-
A high yielding synthesis of the pentacyclic diene-dione 1 has enabled investigation of its reactivity as a double dienophile in Diels- Alder [4+2] cycloadditions with isobenzofuran, leading to novel and highly symmetrical three-sided cavitands 3 and 4.
- Stoermer, Martin J.,Butler, Douglas N.,Warrener, Ronald N.,Weerasuria,Fairlie, David P.
-
p. 2068 - 2071
(2007/10/03)
-
- Stereochemical assignments by PMR spectroscopy: Methoxybromination in norbornene systems
-
The stereochemistry of methoxybromination of some Diels-Alder adducts with bromine in methanol in the presence of yellow lead oxide/silver nitrate has been studied and assigned with the help of PMR spectroscopy. 6,6-Dimethylfulvene-p-benzoquinone adduct (
- Singh, Ashok Kumar,Yadav, Sudha
-
p. 486 - 489
(2007/10/02)
-
- Stereochemical Assignments of the Addition of Bromine to Olefinic Bonds in Bicyclic Systems by PMR Spectroscopy
-
Stereochemistry of bromine addition to the olefinic bonds in cyclopentadiene-p-benzoquinone (I) and anthracene-p-benzoquinone (II), the Diels-Alder adducts and 3',6'-diacetoxybenzonorbornadiene (III) has been assigned with the help of PMR spectroscopy.Cyclopentadiene-p-benzoquinone endo-adduct (I) undergoes exo-cis-addition to yield 5,6-dibromo product (IV) whereas anthracene-p-benzoquinone adduct (II) gives the trans-bromo product (VI).Cyclohexanedione ring of the dienophilic moiety in the latter compound has been proposed a preferred chair-type conformation with two axial bromine atoms on the basis of IR and PMR spectra. 3',6'-Diacetoxybenzonorbornadiene (III) gives the rearranged 2,7-dibromo product (VII).
- Singh, Narain,Verma, Shiva M.
-
p. 290 - 292
(2007/10/02)
-