biostudies-literatureUnknown60(41)Wang XA series of alkyl-subsituted dienyltriphenylarsonium ylides were synthesized and used as monomers in borane-initiated polymerization to obtain practically pure C5-polymers (main-chain grows by five carbon atoms at a time). The impact of triethylborane (Et<sub>3</sub> B), tributylborane (Bu<sub>3</sub> B), tri-sec-butylborane (s-Bu<sub>3</sub> B), and triphenylborane (Ph<sub>3</sub> B) initiators on C5 polymerization was studied. Based on NMR and SEC results, we have shown that all synthesized polymers have C5 units with a unique unsaturated backbone where two conjugated double bonds are separated by one methylene. The synthesized C5-polymers possess predictable molecular weights and narrow molecular weight distributions (M<sub>n,NMR</sub> =2.8 -11.9 kg mol<sup>-1</sup> , Ð=1.04-1.24). It hAngewandte Chemie (International ed. in English)22469-22477https://www.ebi.ac.uk/biostudies/studies/S-EPMC8518972biostudies-literatureSteric Hindrance Drives the Boron-Initiated Polymerization of Dienyltriphenylarsonium Ylides to Photoluminescent C5-Polymers.PMC8518972Hadjichristidis NWang XfalseSteric Hindrance Drives the Boron-Initiated Polymerization of Dienyltriphenylarsonium Ylides to Photoluminescent C5-Polymers.A series of alkyl-subsituted dienyltriphenylarsonium ylides were synthesized and used as monomers in borane-initiated polymerization to obtain practically pure C5-polymers (main-chain grows by five carbon atoms at a time). The impact of triethylborane (Et<sub>3</sub> B), tributylborane (Bu<sub>3</sub> B), tri-sec-butylborane (s-Bu<sub>3</sub> B), and triphenylborane (Ph<sub>3</sub> B) initiators on C5 polymerization was studied. Based on NMR and SEC results, we have shown that all synthesized polymers have C5 units with a unique unsaturated backbone where two conjugated double bonds are separated by one methylene. The synthesized C5-polymers possess predictable molecular weights and narrow molecular weight distributions (M<sub>n,NMR</sub> =2.8 -11.9 kg mol<sup>-1</sup> , Ð=1.04-1.24). It h2021-01-01T00:00:00Z2021 Oct2025-04-19T15:10:43.169Z2025-04-19T15:10:43.169ZS-EPMC85189723438791910.1002/anie.202109190