Synthesis of Linear α-Olefins via Polyhomologation

Linear α-olefins (LAOs) of controlled molecular weight and low PDI were synthesized in high yield by the polyhomologation reaction of dimethylsulfoxonium methylide ( 1 ) with triallylborane ( 2 ). Following polymerization, propionic acid or trimethylamine N -oxide dihydrate (TAO) was used to afford α-vinyl-ω-methyl or α-vinyl-ω-hydroxy end-functionalized polymethylene, respectively. Controllable molecular weights up to 13 kDa were obtained by varying the initial monomer/catalyst ratio, and the resultant polymers had very narrow polydispersities (PDI < 1.08). Although polymer yields were generally high, quantities of oxidized side products were observed in α-vinyl-ω-methyl samples; however, these oxidized side products could be removed for samples of low molecular weights (C n ≤ 36).