Bonding, norbornadiene quadricyclane system

One of the interesting molecules that has been studied in considerable detail is nor-bomadiene (80). Much of this interest has been associated with the interactions between the double bonds of the system. Thus irradiation affords quadricyclane (81). This area of study will be discussed later in this chapter. The radical cation 82 can also be formed from both norbornadiene and quadricyclane by irradiation in acetonitrile/methanol solution with the DCB/phenanthrene sensitizer system. Several products (Scheme 2) are formed in low yield and it should be noted that there is little difference in the yields of products obtained from either starting material. However, it is evident that attack by methanol occurs from the exo face. ... 

Kutal, C., Photochemistry of transition metal-organic systems. Coord. Chem. Rev., 64,191-206,1985. Cuppoletti, A., Dinnocenzo, J.P., Goodman, J.L., and Gould, I.R., Bond-coupled electron transfer reactions photoisomerization of norbornadiene to quadricyclane, /. Phys. Chem. A, 103, 11253-11256,1999. 

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