α‐exomethylene lactone possessing acetal–ester linkage: Polymerization and postpolymerization modification for water‐soluble polymer

Abstract

2,6‐Dimethyl‐5‐methylene‐1,3‐dioxa‐4‐one (DMDO), a cyclic acrylate possessing acetal–ester linkage, was obtained as a mixture of cis‐ and trans‐isomers (95:5) from Baylis–Hillman reaction of an aryl acrylate. The radical and anionic polymerizations of DMDO yielded the corresponding vinyl polymers without any side reactions such as cleavage of the acetal–ester linkage. The polymerization behaviors were significantly different from that of the acyclic acrylate, α‐(hydroxymethyl)acrylic acid, which was expected inactive against polymerization due to the steric hindrance around the vinylidene group by the α‐substituent. The acetal–ester linkage of the obtained polymer (P1) was completely cleaved via acid hydrolysis to afford a water soluble polymer, P2. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 955–961

Synthesis of Thermo-Responsive Polymer via Radical (Co)polymerization of N,N-Dimethyl-α-(hydroxymethyl)acrylamide with N,N-Diethylacrylamide

“…Recently, we have been interested in the polymerization chemistry of α-functionalized acrylates, because the α-functionality affects both the polymerization behavior and the properties of the resulting polymer [ 16 , 17 , 18 , 19 , 20 ]. For example, ethyl α-(aminomethyl)acrylate forms an intramolecular hydrogen bond with the carbonyl group, which reduces the nucleophilicity of the amino group and stabilizes the monomer against the ester-amide exchange reaction [ 19 ].…”

Radical polymerization of ‘dehydroaspirin’ with the formation of a hemiacetal ester skeleton: a hint for recyclable vinyl polymers

“…Recently, our group has focused on the polymerization chemistry of α-functionalized acrylates, [31][32][33][34] which produce polymers that exhibit excellent degradability. 34 As an example, a cyclic acrylate (i.e.…”

“…an exo-methylene lactone) with hemiacetal ester linkages was found to undergo either radical or anionic polymerization to afford the corresponding vinyl polymer, which was subsequently converted to a water-soluble version via hydrolysis of the hemiacetal ester groups. 32 We are also interested in the analogous monomer 2-methylene-4Hbenzo[d] [1,3]dioxin-4-one (MBDO), which does not carry a hemiacetal ester moiety but can produce such groups through radical polymerization. In our initial plan, we had expected the acid hydrolysis of the resulting polymer should afford a polyketone with 1,3-dicarbonyl skeletons.…”

“…Therefore, MBDO has higher reactivity than VAc. The vinyl polymerization of MBDO generates a hemiacetal ester skeleton that can be cleaved by heat [37][38][39][40] and Brønsted 32 or Lewis 41 acids. However, the DTA curve acquired from poly(MBDO) did not exhibit any peaks [Figure 3(a)], prior to the onset of mass loss (T d ) at 232 °C, while the glass transition temperature (T g ) was observed at 132 °C in DSC curve [Figure 3(b)].…”

Hemiacetal Ester Exchanges, Study of Reaction Conditions and Mechanistic Pathway

“…The hydrophilic acidic group was then regenerated by hydrolysis in acidic medium (HCl 5 M) to yield an amphiphilic polymer otherwise difficult to prepare. Since then, this hydrolysis reaction was used in other studies to form water-soluble [12] and alternative [13] copolymers, but also de-crosslinkable [14,15] or recyclable/degradable [16,17] polymers.…”