87268-49-3Relevant academic research and scientific papers
Remote substituent effects upon the rearrangements of housane cation radicals
Gerken, James B.,Wang, Selina C.,Preciado, Alejandro B.,Park, Young Sam,Nishiguchi, Gisele,Tantillo, Dean J.,Little, R. Daniel
, p. 4598 - 4608 (2005)
The rearrangement of a series of housane-derived cation radicals was investigated. Surprisingly, 2-aryl-substituted systems rearranged regioselectively and in a process whose selectivity proved to be independent of the electronic character of para substit
Diastereo- and regioselective synthesis of diquinanes and related systems from tricyclo[3.3.0.02,4]octanes by chemical electron transfer (CET)
Adam,Heidenfelder,Sahin
, p. 1163 - 1170 (2007/10/02)
A new synthetic methodology for diquinanes by one-electron oxidation of tricyclo[3.3.0.02,4]octanes and subsequent stereocontrolled rearrangement is provided. The latter compounds are conveniently accessible through acid-catalyzed isopyrazole cycloaddition, followed by hydrogenation and photoextrusion of molecular nitrogen. The oxidative rearrangement of the tricyclooctanes proceeds catalytically and cleanly to afford regio- and diastereoselectively the corresponding diquinanes.
Azo Bridges from Azines, VI. - Substituted Isopyrazoles as Electron-deficient Dienes for the Synthesis of 2,3-Diazabicycloheptenes and their Photochemistry
Beck, Karin,Huenig, Siegfried
, p. 477 - 484 (2007/10/02)
The ++2> cycloaddition of isopyrazoles (4H-pyrazoles) 3c-e and cyclopentadiene, norbornene, and norbornadiene leads to the azo-bridged products 5, 8, 11, and 12c-e.Irradiation of 5e, 8e, and 11e expectedly produces the tricycles 13, 15, and 17 by loss of nitrogen.In contrast, as a result of the parallel arrangement of the C=C/N=N bonds, the isomers 12c-e are transformed nearly quantitatively into diazetidines 14, 16, and 18; despite the pronounced photolability of the diazabicycloheptene moiety in 12, cycloaddition is preferred over nitrogen elimination.
REARRANGEMENTS AND CYCLIZATION-XVII. MECHANISM OF THE FORMATION OF 1,2-AZOLES IN REACTIONS OF 1,1-DIACYCLOPROPANES WITH HYDRAZINE AND HYDROXYLAMINE DERIVATIVES
Zefirov, Nikolai, S.,Kozhushkov, Sergei, I.,Kuznetsova, Tamara, S.,Ershov, Boris, A.,Selivanov, Stanislav, I.
, p. 709 - 713 (2007/10/02)
The mechanism of recently discovered ring-opening reactions of 1,1-diacyclopropanes with hydrazine and hydroxylamine derivatives is investigated using the 1H-NMR flow (and stopped-flow) method and transient formation of spiro-activated intermediates of th
OPENING OF THE THREE-MEMBERED RING IN 1,1-DISUBSTITUTED CYCLOPROPANES AS A METHOD FOR THE SYNTHESIS OF FUNCTIONAL DERIVATIVES OF PYRAZOLE AND ISOXAZOLE
Zefirov, N. S.,Kozhushkov, S. I.,Kuznetsova, T. S.
, p. 644 - 650 (2007/10/02)
The reaction of 1,1-diacylcyclopropanes with hydrazine and hydroxylamine derivatives, which leads to nucleophilic opening of the three-membered ring and the formation of pyrazole and isoxazole derivatives, was studied.The dependence of the occurrence of t
