FORMATION OF BROMOHYDRINS AND EPOXIDES FROM 4-HYDROXY-2-OXABICYCLO[3.3.0]OCT-7-EN-3-ONE AND 9-HYDROXY-7-OXABICYCLO[4.3.0]NON-4-EN-8-ONE

The hydroxy lactone 1 and the silylated derivative 8 react selectively with HOBr to give access to polyfunctional bicyclic systems such as the bromo eater 10. The lactone 3 or the corresponding derivative 20 react less selectively to give mixtures of compounds 16, 17, 18, 19, 21, 22. The hydroxybicyclo[4.3.0]nonenones 2 and 4 behave in a similar fashion to the lactone 3, reacting nonselectively with HOBr and m-chloroperbenzoic acid to produce a plethora of highly substituted bicycle compounds 23-31, 33-39, 41 and 42. X-Ray crystal structures were obtained for four compounds, the diacetates 25 and 37 and the epoxides 26 and 27.