Maleimide-functionalized poly(2-ethyl-2-oxazoline): synthesis and reactivity

Abstract

Poly(2-ethyl-2-oxazoline)s (PEtOx₂₃ – M_n = 2300 g mol⁻¹, Đ = 1.07; PEtOx₄₆ – M_n = 4400 g mol⁻¹, Đ = 1.06) end-functionalized with a maleimide moiety were prepared from azide-terminated PEtOx_x-N₃via copper-catalyzed azide–alkyne cycloaddition (CuAAC) with an alkyne-bearing maleimide (MI). The latter has been synthesized in a three-step procedure, including protection of the maleimide double bond prior to the modification of PEtOx. PEtOx_x-MI was characterized by NMR (¹H, ¹³C), SEC, FT-IR, and MALDI-ToF MS and, after deprotection of the maleimide, used in nitrile imine-mediated tetrazole-ene cycloaddition (NITEC) processes for covalent attachment to silicon surfaces in a grafting-to approach.