Research Information System
Tetrahedron, vol.50, no.35, pp.10555-10578, 1994 (Scopus)
The electrophilic addition of bromine to benzobarrelene in chloroform at 10° C followed by repeated chromatography combined with fractional crystallization allowed us to isolate ten products 12-21 Structural determination of these compounds revealed that the barrelene skeleton was rearranged completely. 18-21 are alcohol compounds which arise from hydrolysis of 12, 13, 14, and 15, respectively. High temperature bromination of benzobarrelene in decalin at 150 °C followed by repeated chromatography combined with fractional crystallization gave us 18 products. Nonrearranged products 24, 25, and 26 have been isolated in 50% yield. All compounds have been characterized properly, especially by 200 MHz 1H NMR and 50 MHz 13C NMR spectra. Furthermore, it has been concluded that high temperature bromination of bicyclic systems gives more non-rearranged products. If the molecule is more strained, the tendency to rearrange decreases as in the case of benzonorbornadiene. © 1994.