A. Burritt et al., BROMINATION OF EXO-TRICYCLO[3.2.1.0(2,4)]OCTANE AND ENDO-TRICYCLO[3.2.1.0(2,4)]OCTANE, Journal of organic chemistry, 60(9), 1995, pp. 2812-2819
Reaction of exo-tricyclo[3.2.1.0(2,4)]octane with bromine in CCl4 or m
ethanol proceeds, at least in part, by way of a classical ion to give
1,3-addition products. Electrophilic attack by bromine occurs with inv
ersion at the corner to the C2C4 bond and nucleophilic attack by both
inversion and retention. In methanol the initial cation species is suf
ficiently short lived that it does not relax to the classical cation,
and nucleophilic attack with inversion competes with skeletal rearrang
ement. Reaction of endo-tricyclo[3.2. 1.0(2,4)]octane with bromine in
CCl4 gives 1,3-addition and an addition rearrangement product which ar
e formed with inversion at the site of both electrophile and nucleophi
le attack. A further dibromide product is observed, the formation of w
hich is suppressed in methanol. In methanol nucleophilic attack occurs
with inversion to give a mixture of 1,3-addition and rearrangement pr
oducts.