M. Oda et al., STRUCTURAL REVISION OF THE CYCLOADDUCT OF BICYCLO[5.3.0]DECA-1(7),2,4-TRIENE-10-ONE WITH 4-PHENYL-1,2,4-TRIAZOLINE-3,5-DIONE, Recueil des travaux chimiques des Pays-Bas, 115(2), 1996, pp. 151
Cycloaddition reaction of 4-phenyl-1,2,4-triazoline-3,5-dione(PTAD) to
bicyclo[5.3.0]deca-1 (7),2,4-trien-10-one (3) was reinvestigated. In
various conditions, the reaction afforded solely 1:1 cycloadduct as re
ported. The structure of this adduct, previously thought to be a forma
l [6+2] adduct, was revised. This adduct is now thought to be a cycloh
eptatriene-derived [4+2] adduct on the basis of extensive H-1- and C-1
3-NMR studies.