69994-29-2Relevant academic research and scientific papers
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.
