General. Starting materials 1-4 were prepared by the reaction of dibromocarbene with the appropriate olefins according to known procedure^.^ endo-9-Bromobicyclo [6. lO] nonane (1 1) was obtained from reduction of 1 with tri-n-butyltin hydride! Silver tosylate was prepared from silver oxide and p-toluenesulfonic acid, according to the procedure of Kornblum et all0 NMR spectra were obtained on a Varian T-60 spectrometer using MedSi as an internal ...
