Amine-Catalyzed Chain Polymerization of Ethyl Glyoxylate from Alcohol and Thiol Initiators

Hewitt, David; Grubbs, Robert B.

doi:10.1021/acsmacrolett.0c00865

Cited by 7 publications

(6 citation statements)

References 53 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thiols on the other hand are more acidic (p K a ∼11 in H 2 O) and more nucleophilic than alcohols (aliphatic alcohols: p K a ∼16) and could be partially deprotonated with weak bases like commonly used triethylamine and diisopropyl ethylamine (e.g., Et 3 NH + , p K a 10.75). Hewitt and Grubbs recently reported the successful initiation of ethyl glyoxylate polymerization with 4-methoxybenzyl thiol using triethylamine as a base …”

Section: Resultsmentioning

confidence: 99%

“…Hewitt and Grubbs recently reported the successful initiation of ethyl glyoxylate polymerization with 4methoxybenzyl thiol using triethylamine as a base. 22 We started with tetrathiol C1 and triethylamine in CH 2 Cl 2 at −20 °C for polymerization, which led to successful polymerization (Figure 1). 9 The polymer was capped with benzyl chloroformate (CBZ-Cl) as a model EC, giving starshaped PEtG with M n 18.0 kDa and Đ 1.20.…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

See 1 more Smart Citation

Acid-Responsive Poly(glyoxylate) Self-Immolative Star Polymers

et al. 2021

View full text Add to dashboard Cite

Self-immolative polymers have significant potential for applications such as drug or gene delivery. However, to realize this potential, such materials need to be customized to respond to specific variations in biological conditions. In this work, we investigated the design of new star-shaped self-immolative poly(ethyl glyoxylate)s (PEtGs) and their incorporation into responsive nanoparticles. PEtGs are a subclass of stimulus-responsive self-immolative polymers, which can be combined with different stimuli-responsive functionalities. Two different tetrathiol initiators were used for the polymerization in combination with a variety of potential pH-responsive end-caps, yielding a library of star PEtG polymers which were responsive to pH. Characterization of the depolymerization behavior of the polymers showed that the depolymerization rate was controlled by the end caps rather than the architecture of the polymer. A selection of the star polymers were modified with amines to allow introduction of charge-shifting properties. It was shown that pH-responsive nanoparticles could be prepared from these modified polymers and they demonstrated pH-dependent particle disruption. The pH responsiveness of these particles was studied by dynamic light scattering and 1H nuclear magnetic resonance spectroscopy.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: ■ Experimental Sectionmentioning

confidence: 99%

Acid-Responsive Poly(glyoxylate) Self-Immolative Star Polymers

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Recently, multiple measures have been taken to develop poly(acetal-ester)s and polyacetals. [24][25][26][27][28][29][30][31] 2-Methyl-1,3-dioxane-4one (MDO) as a kind of cycloacetal ester has both an ester group and an acetal bond, [32][33][34][35][36] and showed an unprecedented result during its Et 2 Zn catalyzed ROP, where poly(hemiacetal ester) (PMDO) was obtained at a low ratio of catalyst/initiator (low [Zn]) and the polyester (P3HP) was obtained at a high ratio of catalyst/initiator (high [Zn]). MDO as an alternative β-PL is accessible for the synthesis of P3HP.…”

Section: Introductionmentioning

confidence: 99%

Ring opening copolymerization of δ-valerolactone with 2-methyl-1,3-dioxane-4-one towards poly(3-hydroxypropionate-co-5-hydroxyvalerate) copolyesters

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Polyglyoxylate (PG) SIPs have been of particular interest to our group. ,,, The monomer ethyl glyoxylate can be obtained from commercial sources for the preparation of poly(ethyl glyoxylate) (PEtG) through proton-transfer-mediated , or anionic polymerization . PEtG has been synthesized to incorporate different end-caps that are responsive to light, heat, thiols, and hydrogen peroxide .…”

Section: Introductionmentioning

confidence: 99%

Polyglyoxylamides with a pH-Mediated Solubility and Depolymerization Switch

et al. 2021

View full text Add to dashboard Cite

Self-immolative polymers (SIPs) are characterized by their ability to depolymerize in response to the cleavage of a single end-cap or backbone moiety, making them attractive for numerous applications including sensors, transient plastics, and delivery vehicles. For many applications, it would be desirable to have an SIP capable of depolymerizing selectively under mildly acidic aqueous conditions. However, the poor solubility of most SIPs in water, accompanied by the competing effects of end-cap cleavage and depolymerization mechanisms, has made this a challenge. Here, we describe the development of polyglyoxylamides (PGAms) with pendent amino groups to achieve solubility switching at mildly acidic pH, which allows access of water to the end-cap and consequently depolymerization. PGAms with varying amino groups were synthesized from trityl end-capped poly(ethyl glyoxylate) (PEtG). While water-insoluble PEtG underwent no detectable depolymerization between pH 5 and 7.4 and water-soluble PGAms underwent rapid depolymerization regardless of pH in this range, a PGAm with N,N-diisopropylaminoethyl (DPAE) pendent groups underwent more rapid depolymerization at pH 5−6 compared to pH 7.4. PGAms were also incorporated into block copolymers with poly(ethylene glycol) (PEG). Nanoassemblies formed from PEG-PGAm(DPAE), swelled, disassembled, and depolymerized as the pH was lowered from 8 to 5. Copolymers lacking a solubility switch did not undergo pH-dependent disassembly or depolymerization. Overall, this work provides a new platform approach for the development of pH-sensitive SIP materials for a wide range of applications.

show abstract

Amine-Catalyzed Chain Polymerization of Ethyl Glyoxylate from Alcohol and Thiol Initiators

Cited by 7 publications

References 53 publications

Acid-Responsive Poly(glyoxylate) Self-Immolative Star Polymers

Acid-Responsive Poly(glyoxylate) Self-Immolative Star Polymers

Ring opening copolymerization of δ-valerolactone with 2-methyl-1,3-dioxane-4-one towards poly(3-hydroxypropionate-co-5-hydroxyvalerate) copolyesters

Polyglyoxylamides with a pH-Mediated Solubility and Depolymerization Switch

Contact Info

Product

Resources

About