INITIATION VIA HALOBORATION IN LIVING CATIONIC POLYMERIZATION. 5. FACILE SYNTHESIS OF SEC-AMINE FUNCTIONAL POLYISOBUTYLENES

Abstract

The synthesis of sec-amine terminated telechelic polyisobuty-lene (PIB) has been accomplished by reacting n-butyl azide with the dichloroboron head group of PIB obtained by polymerization of isobutylene (IB) via haloboration-initiation. The facile, one-pot reaction resulted in complete conversion of the PIB dichloroboron head groups into butyl amino termini even at room temperature. The reaction is rapid and can be further accelerated by increasing the concentrations and/or the solvent polarity. The applicability of this head functionalization in the synthesis of asymmetric telechelic polymers is demonstrated through the synthesis of α-sec-amino-ω-tert-chloro and α-sec-amino-ω-methoxy-carbonyl PIB’s. Telechelic α,ω-di-sec-amino PIB was also prepared by the combination of haloboration-initiation and living coupling reaction with 2,2-bis[4-(1-tolylethenyl)phenyl]-propane (BDTEP).

Keywords:

• PIB
• Telechelic
• Haloboration-Initiation
• Dichloroborane
• Azide
• Sec-amine
• NMR

ACKNOWLEDGMENTS

Support by the National Science Foundation (DMR-9502777) is gratefully acknowledged.