73249-32-8Relevant articles and documents
Reactions and Rearrangements of 5,6-Disubstituted Bicyclohexenes
Roth, Ronald J.,Katz, Thomas J.
, p. 961 - 965 (2007/10/02)
Halogenation of benzvalene (I) with either Br2 or Cl2/CCl4 gives only one adduct, anti,syn-5,6-dihalobicyclohexene, IIa or IIb.This adduct is thermally unstable and rearranges to exo,anti-4,6-dihalobicyclohexene, IIIa or IIIb (half-life at 50 deg C for IIa = 18 min; for IIb = 77 min).Treatment of IIb with 1 equiv of KCN in aqueous acetonitrile gives anti,syn-5-chloro-6-cyanobicyclohexene (IIc) and endo,endo-3,5-dicyanotricyclo2.6>hexane (IVa).IIc slowly rearranges to 6-anti-chloro-4-exo-cyanobicyclohexene (IIIc) (calculated half-l ife at 50 deg C = 1E5 min).The mechanism of the rearrangement of IIa-c to IIIa-c in light of kinetic and deuterium-labeling data as well as the mechanism of formation of IIc is discussed.When treated with KOAc in aqueous acetonitrile or AgOAc in benzene, IIb gives endo,endo-3,5-diacetoxytricyclo2.6>hexane (IVb).When IVb is treated with HCl/CCl4, it rearranges to anti,syn-5,6-diacetoxybicyclohexene (IId).When heated, both IId and IVb rearrange to exo,anti-4,6-diacetoxybicyclohexene (IIId).In contrast, IVa is thermally stable and does not rearrange in acid.
