New aldehyde‐functional methacrylic water‐soluble polymers

Aldehyde groups enable facile conjugation to proteins, enzymes, oligonucleotides or fluorescent dyes, yet there are no literature examples of water‐soluble aldehyde‐functional vinyl monomers. We report the synthesis of a new hydrophilic cis‐diol‐based methacrylic monomer (GEO5MA) by transesterification of isopropylideneglycerol penta(ethylene glycol) using methyl methacrylate followed by acetone deprotection via acid hydrolysis. The corresponding water‐soluble aldehyde monomer, AGEO5MA, is prepared by aqueous periodate oxidation of GEO5MA at 22 °C. RAFT polymerization of GEO5MA yields the water‐soluble homopolymer, PGEO5MA. Aqueous periodate oxidation of the terminal cis‐diol units on PGEO5MA at 22 °C affords a water‐soluble aldehyde‐functional homopolymer (PAGEO5MA). Moreover, a library of hydrophilic statistical copolymers bearing cis‐diol and aldehyde groups was prepared using sub‐stoichiometric periodate/cis‐diol molar ratios. The aldehyde groups on PAGEO5MA homopolymer were reacted in turn with three amino acids to demonstrate synthetic utility.
A water‐soluble aldehyde monomer (AGEO5MA) was prepared by oxidation of GEO5MA at 22 °C. RAFT aqueous polymerization yielded PAGEO5MA homopolymer, which was oxidized using sub‐stoichiometric periodate/cis‐diol molar ratios to yield hydrophilic statistical copolymers with cis‐diol and aldehyde groups. Three PGEO5MA‐based diblock copolymers were converted into aldehyde‐functional copolymers, which were derivatized with amino acids.