Investigation of 1,1‐diphenylethylene Oligomerization in the End‐Capping Reaction of Poly(styryl)lithium

Summary: The possible oligomerization of 1,1-diphenylethylene (DPE) in the end-capping reaction of poly(styryl)lithium (PSLi) was studied in hydrocarbon solvents using excess DPE (≤16 mol-eq); the effect of addition of THF (30 mol-eq Lewis base) and extended times of reaction (8-24 h) were also investigated. The characterization of the polymers was made by size exclusion chromatography (SEC), proton nuclear magnetic resonance spectroscopy (1H NMR) and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS). MALDI- TOF mass spectrometric results revealed the absence of DPE oligomerization under the reaction conditions used in this study.