81599-81-7Relevant academic research and scientific papers
-Cycloaddition of Singlet Oxygen and Phenyltriazolinedione with Bicyclonona-2,4,6-triene and Derivatives
Adam, Waldemar,Cueto, Omar,Lucchi, Ottorino De
, p. 1170 - 1177 (2007/10/02)
The dienic reactivity of the bicyclononatrienes 1a (-isomer) and 1b (-isomer) and its oxa-derivative 6 (cyclooctatetraene epoxide) as well as 1,3,5-cyclooctatrienone (7), towards singlet oxygen (1O2) and phenyl-1,2,4-triazoline-3,5-dione (PTAD) as dienophiles has been investigated.Except for 1a, which affords the endoperoxide 9a in 60percent yield, the remaining substrates 1b, 6, and 7 do not react with 1O2.With PTAD 1a, 1b, 6, and 7 afford the urazoles 10a, 8b, 12c, and 11, respectively.Unusual is the fact that the bicyclotriene 1b leads only to the tri cyclic urazole 8b, the first example of this type of -cycloadduct of 1b, while the oxa-analog 6 affords only the tetracyclic urazole 12c.Moreover, 6 reacts with PTAD considerably more sluggishly than 1b.
