Results Bromination. Brominations of hydrocarbons 2-5 were carried out with bromine in CH2C12 at room temperature. The reactions were worked up immediately after loss of color which required only 10-15 min. In all cases the reactions were highly regioselective, affording predominantly a single isomeric monobromo-substituted product. The positions of substitution were determined by direct analysis of the high-resolution proton NMR ...