نتایج جستجو برای: fetraaza bicyclo 330 octane
تعداد نتایج: 11654 فیلتر نتایج به سال:
The title compound, C(22)H(28)O(4), is composed of a central octa-decane ring and two spiro-[bicyclo-[2.2.1]hept[2]ene-7,2'-[1,3]dioxolane] units. This polycycle has pseudo twofold symmetry and the central cyclo-octane ring has a distorted boat configuration.
Cross-conjugated trienamines are introduced as a new concept in asymmetric organocatalysis. These intermediates are applied in highly enantioselective Diels-Alder and addition reactions, providing functionalized bicyclo[2.2.2]octane compounds and γ'-addition products, respectively. The nature of the transformations and the intermediates involved are investigated by computational calculations an...
A 4-(pyrrolidin-1-yl)phenyl electron donor and 10-cyanoanthracen-9-yl electron acceptor are attached via alkyne linkages to the bridgehead carbon atoms of bicyclo[2.2.2]octane and all three benzo-annulated bicyclo[2.2.2]octanes. The sigma-system of bicyclo[2.2.2]octane provides a scaffold having nearly constant bridge geometry on which to append multiple, weakly interacting benzo pi-bridges, so...
The total synthesis of sculponeatin N, a bioactive polycyclic diterpene isolated from Isodon sculponeatus, is reported. Key features of the synthesis include diastereoselective Nazarov and ring-closing metathesis reactions, and a highly efficient formation of the bicyclo[3.2.1]octane ring system by a reductive radical cyclization.
A series of ethanodiazapolycenes were prepared in 87%-89% yields by Friedländer reactions of three o-aminoarenecarbaldehydes with bicyclo[2.2.2]octane-2,5-dione and their spectral, thermal, and structural properties were studied. Subsequent attempts to convert them to diazapolycenes have proved unsuccessful.
The crystal structures of 7,7-dicyclobutyl-5-hydroxymethyl-6-oxabicyclo[3.2.1]octane-1-carboxylic acid, C17H26O4, (I), and 1-(hydroxymethyl)-7-oxaspiro[bicyclo[3.2.1]octane-6,1'-cyclopentane]-5-carboxylic acid, C13H20O4, (II), determined at 170 K, show that the conformation of the hydroxymethyl group (anti or gauche) affects the dimensionality (one- or two-dimensional) of the supramolecular str...
Selectfluor [1-(chloro methyl) -4-flouro -1,4-di azonia bicyclo[2,2,2] octane bis (tetraflouro-borate)] catalyzed the preparation of quinoxaline and 2,3-dihydo pyrazine derivatives through one -pot condensation of 1,2-di amines with 1,2-di carbonyls in solvent and under solvent- free conditions. This catalyst is commercially available, inexpensive, reusable, stable to air and moisture, and rela...
The title compound, C(16)H(20)Cl(2)O(8), contains a central bicyclo-[2.2.2]octane skeleton with slightly twisted conformation. In this structure, the C-C bond lengths are in the range 1.525 (2)-1.552 (2) Å. Two sides of this skeleton have cis,cis acet-oxy substituents and the Cl atoms have a trans arrangement. An extensive network of weak C-H⋯O interactions stabilizes the crystal structure.
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید