Quantitative amine functionalization of polymeric organolithium compounds with 3-dimethylaminopropyl chloride in the presence of lithium chloride

The addition of lithium chloride promoted the coupling reaction of hydrocar bon solutions of poly(styryl)lithium (PSLi) and poly(isoprenyl)lithium (PIL i) with 3-dimethylaminopropyl chloride to form the correspending omega-dime thylamino-functionalized polymers. Quantitative amine functionalization was achieved for PSLi and PILi in the presence of I and 10 equivalents, respec tively, of Lid in benzene; the functionalization efficiency was only 67% fo r PSLi and 85% for PILi in the absence of LiCl. The polymer products were c haracterized by size exclusion chromatography, thin-layer chromatography, a nd amine end-group titration. The pure amine-functionalized polymers were i solated by silica gel column chromatography. (C) 2000 John Wiley & Sons, In c.