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Title: The Anionic Polymerization of a tert-Butyl-Carboxylate-Activated Aziridine
N-Sulfonyl-activated aziridines are known to undergo anionic-ring-opening polymerizations (AROP) to form polysulfonyllaziridines. However, the post-polymerization deprotection of the sulfonyl groups from polysulfonyllaziridines remains challenging. In this report, the polymerization of tert-butyl aziridine-1-carboxylate (BocAz) is reported. BocAz has an electron-withdrawing tert-butyloxycarbonyl (BOC) group on the aziridine nitrogen. The BOC group activates the aziridine for AROP and allows the synthesis of low-molecular-weight poly(BocAz) chains. A 13C NMR spectroscopic analysis of poly(BocAz) suggested that the polymer is linear. The attainable molecular weight of poly(BocAz) is limited by the poor solubility of poly(BocAz) in AROP-compatible solvents. The deprotection of poly(BocAz) using trifluoroacetic acid (TFA) cleanly produces linear polyethyleneimine. Overall, these results suggest that carbonyl groups, such as BOC, can play a larger role in the in the activation of aziridines in anionic polymerization and in the synthesis of polyimines.  more » « less
Award ID(s):
1919906
PAR ID:
10389871
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Polymers
Volume:
14
Issue:
16
ISSN:
2073-4360
Page Range / eLocation ID:
3253
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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