Abstract
The linking of macroanions with BF
3
OEt
2
leads to a 3-arm star with a boron junction point, which can serve as a macroinitiator for the polyhomologation of dimethylsulfoxonium methylide, thus enabling the synthesis of novel but not “stable” polyethylene (PE)-based 3-arm star block copolymers. Taking advantage of the “stitching” reaction, which transforms the “unstable” boron junction to “stable” carbon, we were able to synthesize novel star block copolymers. This strategy is general and opens new horizons towards unprecedented PE-based materials.