Stilbene → 1,1-Diphenylethylene

Participants

Reaction Steps

For instance, in accordance with an embodiment of the present inveniton, a living macrocarbocation, e.g., living cationic polyisobutylene, is reacted with a double diphenylethylene, e.g., 1,3-bis(1-phenylethenyl)benzene (sometimes referred to as meta-double diphenylethylene) or 1,4-bis(1-phenylethenyl)benzene (sometimes referred to as para-double diphenylethylene), to produce a 1,1-diphenylethylene end-functionalized carbocationic polymer. The carbocation is then alkylated with a suitable alkylating agent, e.g., with an organometallic compound such as dimethylzinc, whereupon the resulting macromonomer is readily metallated with a suitable organometallic compound such as an alkyllithium compound, thereby providing a living anionic macroinitiator in near quantitative yield. A sterically hindered lithium compound, e.g., a 1,1-diphenylalkyllithium species, is used in certain embodiments to remove impurities that may be present alongside the 1,1-diphenylethylene end-functionalized polymer, thereby preventing premature termination of the living macroanion.

Provenance & Evidence