Using the easily accessible 2-azaallyl anions as initiators, the one-pot synthesis of well-defined primary amine-ended telechelic polyaziridines (α-NH2 PAzs) has been achieved through the ring-opening polymerization (ROP) of N-sulfonyl aziridines followed by hydrolysis of the diphenylketimine moiety (NCPh2). The 2-azaallyl anions were synthesized from the reaction of diphenylketimine or N-[aryl-methylene]-α-phenylbenzenemethanamine with potassium bis­(trimethylsilyl) amide (KHMDS) in situ and used to initiate the ROP of aziridines leading to well-defined α-(Ph2CN)-α′-aryl-ω-NH PAzs. Along with the diphenylketimine group (NCPh2), aryl functionalities, such as pyridine and triphenylphosphine moieties, can also be incorporated to the chain end. Chain extension has been applied for the synthesis of poly­(N-sulfonyl aziridine)-block-poly­(ε-caprolactone) (PAz-b-PCL) block copolymers by utilization of the primary amine end group as initiating sites for the ROP of ε-caprolactone catalyzed by tin 2-ethyl hexanoate (SnOct2). Taking advantage of this synthetic approach, core cross-linked multiarm star (CCS) polymers with an outermost shell having amino and triphenylphosphine functionalities have been synthesized via “arm-first” strategy.

A highly easy and efficient metal-free methodology for the synthesis of polyaziridine-based polymers with controlled architectures and desired functionalities was developed by organocatalytic ring-opening polymerization (ROP) of N-sulfonyl aziridines with a carboxylic acid as initiator. 1,5,7-Triaza­bicyclo[4.4.0]­dec-5-ene (MTBD) and phosphazene t-Bu-P4 organocatalysts have demonstrated high catalytic efficiency in connection with the controlled/living character of the ROP of 2-methyl-N-tosylaziridines (TsMAz) initiated by benzoic acid. Aryl carboxylic acids bearing an azido or a hydroxyl group as well as bio-derived vanillic acid and syringic acid and alkyl- and alkenyl-substituted carboxylic acids, such as acetic acid, palmitic acid, and methacrylic acid, can all initiate the ROP of TsMAz toward well-defined P­(TsMAz)­s. α,ω-Diamino telechelic, star-shaped P­(TsMAz)­s, and poly­(styrene-co-methacrylic acid)-graft-poly­(2-methyl-N-tosylaziridine) [P­(St-co-MAA)-g-P­(TsMAz)] have been conveniently synthesized from the corresponding multicarboxyl (macro)­initiators. Finally, this protocol has been applied for the synthesis of a linear photoresponsive P­(TsMAz) and an aggregation-induced emission (AIE)-active 4-arm P­(TsMAz) star from the corresponding functionalized carboxylic acids.

Sequential ring-opening polymerization of ε-caprolactone (ε-CL)/propylene oxide (PO) and N-sulfonyl aziridine switched by tosyl isocyanate (TSI) allows the metal-free synthesis of polysulfonamide-based copolymers.

An easy, efficient, and solvent/catalyst-free synthetic methodology was developed for the modification of hyperbranched polyethyleneimines (PEI) by ring-opening-addition or ring-opening-polymerization of N-sulfonyl aziridines. Under melting and open-flask conditions, the nucleophilic...

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