Precise Synthesis of Clickable Chiral Poly(n-hexyl isocyanate)s

摘要

Helical polymers,such as polyacetylene and polyisocyanate,have been extensively studied because of their fascinating property.1-2 Recently,we reported the synthesis of the cliekable poly(n-hexyl isocyanate)s (PHICs) with an azido or alkyne group at the α-chain end.3 The obtained clickable PHICs were suitable rod segments for the synthesis of well-defined macromolecular architectures.In this presentation,novel clickable chiral PHICs (PHIC*-N3 and PHIC*-C≡C) with an azido or alkyne end group have been prepared by the living coordination polymerization of n-hexyl isocyanate using (R)-1-azido-3-phenoxy-2-propanoloxy (cyclopentadienyl)titanium (Ⅳ) dichloride (1) or (R)-1-phenoxy-4-pentyn-2-oloxy (cyclopentadienyl)titanium (Ⅳ) dichloride (2) as a catalyst,respectively,as shown in Scheme.The chiral chain end in PHICs had a stereochemical influence upon the helical conformation of the polymer backbone due to the covalent chiral domino effect.Therefore,the clickable chiral PHICs have potential application to the synthesis of well-defined chiral macromolecular architectures.