Hydroboration of 1,2-dimethylcyclopentene with BH3·THF affords a product in which boron migrates stereospecifically at low temperature into the cyclopentane ring. At higher temperatures subsequent (non-stereospecific) isomerisation occurs via a competing reaction mechanism.
                                    1,2-二甲基
环戊烯与BH 3 ·THF的
硼氢化反应生成一种产物,其中
硼在低温下立体定向迁移到
环戊烷环中。在更高的温度下,随后的(非立体特异性)异构化是通过竞争性反应机理发生的。