Institute of Organic Chemistry, Johannes Gutenberg University, Duesbergweg 10-14, 55128, Mainz, Germany.
Graduate School Materials Science in Mainz (MAINZ), Staudingerweg 9, 55128, Mainz, Germany.
Macromol Rapid Commun. 2019 Jun;40(12):e1900057. doi: 10.1002/marc.201900057. Epub 2019 Mar 20.
In contrast to acetal groups, aminal moieties are almost unknown in polymer chemistry. The aminal-protected isopropyl-hexahydro-pyrimidine glycidyl amine (PyGA) for the anionic ring-opening polymerization (AROP) is introduced. The monomer is prepared in a two-step synthesis and can be polymerized in a well-controlled manner under AROP conditions. Several poly(ethylene glycol) block and triblock copolymers are synthesized in a molecular weight range from 2 700 to 11 400 g mol with up to 11 mol% PyGA. The molecular weight distributions are monomodal with low dispersity (Đ = M /M ) below 1.2. After the polymerization, the acid-labile hexahydro-pyrimidine rings can be conveniently cleaved in acidic media, liberating two secondary amines per PyGA monomer unit. The released 1,3-diamine functionalities can be addressed via post-polymerization modification and show complexation of copper(II) ions in aqueous solution. The compounds are promising for water-soluble catalyst systems, the removal of transition metals from water, and as a building block for complexing polyethers for biomedical application.
与缩醛基团相比，亚胺基在聚合物化学中几乎闻所未闻。本文引入了亚胺保护的异丙基-六氢嘧啶基缩水甘油胺（PyGA）作为阴离子开环聚合（AROP）的单体。该单体通过两步合成法制备，在 AROP 条件下可以进行可控聚合。通过 AROP 合成了数种分子量在 2700 至 11400 g/mol 之间、含有多达 11 mol% PyGA 的聚（乙二醇）嵌段和三嵌段共聚物。分子量分布呈单分散性，多分散性指数（Đ = M /M ）低于 1.2。聚合后，在酸性介质中可以方便地裂解不稳定的六氢嘧啶环，每个 PyGA 单体单元释放出两个仲胺。通过聚合后修饰，可以获得 1,3-二胺官能团，并在水溶液中与铜（II）离子络合。这些化合物有望成为水溶性催化剂体系、从水中去除过渡金属以及用于生物医学应用的复杂聚醚的构建块。
