Polyglycidols with two orthogonal protective groups:: Preparation, selective deprotection, and functionalization
Polyglycidols with two orthogonal protective groups:: Preparation, selective deprotection, and functionalization
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DOI：
10.1021/ma0627875
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发表时间：
2007-05-01
期刊：
影响因子：
5.5
通讯作者：
Moeller, Martin
中科院分区：
文献类型：
--
作者：
Erberich, Michael;Keul, Helmut;Moeller, Martin
以3-苯基-1-丙醇钾为引发剂，进行了烯丙基缩水甘油醚（AGE）、叔丁基缩水甘油醚（tBuGE）和乙氧基乙基缩水甘油醚（EEGE）的阴离子开环聚合和共聚合。聚合物poly（AGE）、poly（tBuGE）、poly（EEGE）以及poly（AGE-co-tBuGE）、poly（AGE-co-EEGE）和poly（EEGE-co-tBuGE）具有受控的聚合度、窄的分子量分布和预定的重复单元比例。一级动力学相对于缩水甘油基单体被发现为均聚和共聚。从均聚物中去除保护基团是使用三氟乙酸（用于聚（tBuGE））、盐酸水溶液（用于聚（EEGE））和钯催化剂（用于聚（AGE））来实现的;在所有情况下，获得线性聚（缩水甘油醚）（聚（GE），1）。通过仅选择性除去一个保护基团实现以下转化：使用盐酸水溶液，将聚（AGE-共-EEGE）转化为聚（AGE-共-GE）4;使用三氟乙酸，将聚（AGE-共-tBuGE）转化为聚（AGE-共-三氟乙酸缩水甘油酯），5;和通过使用Pd/C和对甲苯磺酸，将聚（AGE-共-tBuGE）转化为聚（GE-共-tBuGE），3。从聚（EEGE-co-tBuGE）中仅选择性除去一个保护基团是不可能的。用盐酸水溶液或用三氟乙酸处理分别得到聚（GE）1和聚（三氟乙酸缩水甘油酯）2。最后，聚合物聚（GE-co-tBuGE）3和聚（AGE-co-GE）4的游离羟甲基在聚合物类似反应中使用炔丙基溴部分转化为具有缩水甘油基炔丙基醚（GPE）重复单元的相应聚合物。在模型反应中，这些具有GPE重复单元的聚合物之一在（2 + 3）环加成反应中成功地与叠氮基糖部分转化。
Anionic ring-opening polymerization and copolymerization of allyl glycidyl ether (AGE), tert-butyl glycidyl ether (tBuGE), and ethoxyethyl glycidyl ether (EEGE) was performed using potassium 3-phenyl-1-propanol as initiator. The polymers poly(AGE), poly(tBuGE), poly(EEGE) as well as poly(AGE-co-tBuGE), poly(AGE-co-EEGE), and poly(EEGE-co-tBuGE) were obtained with controlled degree of polymerization, narrow molecular weight distribution and a predetermined ratio of repeating units. First-order kinetics with respect to the glycidyl monomers were found for homo- and copolymerization. The removal of protection groups from the homopolymers was achieved using trifluoroacetic acid for poly(tBuGE), aqueous hydrochloric acid for poly(EEGE), and a palladium catalyst for poly(AGE); in all cases a linear poly(glycidyl ether) (poly(GE), 1) was obtained. The following conversions were achieved by selective removal of only one protection group: using aqueous hydrochloric acid, poly(AGE-co-EEGE) was converted to poly(AGE-co-GE) 4; using trifluoroacetic acid, poly(AGE-co-tBuGE) was converted to poly(AGE-co-glycidyl trifluoroacetate), 5; and by using Pd/C and p-toluenesulfonic acid poly(AGE-co-tBuGE) was converted to poly(GE-co-tBuGE), 3. A selective removal of only one protection group from poly(EEGE-co-tBuGE) was not possible. Treatment with aqueous hydrochloric acid or with trifluoroacetic acid lead to poly(GE), 1, and poly(glycidyl trifluoroacetate), 2, respectively. Finally free hydroxymethyl groups of the polymers poly(GE-co-tBuGE), 3, and poly(AGE-co-GE), 4, were partially converted in a polymer analogous reaction using propargyl bromide to the corresponding polymers with glycidyl propargyl ether (GPE) repeating units. In a model reaction one of these polymers with GPE repeating units was successfully converted with an azido sugar moiety in a (2 + 3) cycloaddition reaction.