(1) to allow the polyborylated alkene systems to undergo the EnT step first. (2) the addition reaction of this biradicals into the olefin moiety as incorporating more from the bulkier Bpin groups might increase the steric hindrance in the transition state, (3) the regioselectivity and site-specificity of addition reaction as four isomers can be obtained in this process, (4) precise control of the diastereoselectivity (Figure ).