Convenient Access to α‐Amino‐ω‐Hydroxyl Heterobifunctional peg and ppo via a Sacrificial Hexahydro‐Triazine Star Strategy

oxide) (PPO) in the molecular weight range of 1–5 kg mol

−1

 and low dispersity 

M

w

/

M

n

 

< 1.1. The 

α,ω-heterobifunctional polyethers are valuable structures 

for bioconjugation. Furthermore, an acid-labile triazine star polymer is directly 

used as a polyol component for the synthesis of a polyurethane network, 

which is stable under ambient conditions but degrades rapidly under acidic 

conditions.

Poly(ethylene glycol) (PEG), also known as poly(ethylene 

oxide) (PEO), and the structurally related poly(propylene oxide) 

(PPO) are important materials that are produced on a megaton 

scale.

[1]

 PEG excels in pharmaceutical and biomedical applica-

tions due to its non-toxicity and high solubility in water. The 

related polyether PPO offers other unique properties, such as a 

low glass transition temperature, amorphous structure, that is, 

no melting point, which renders it perfect as a soft segment in 

poly urethane (PU) foams.

[2]

 Heterobifunctional PEG with two 

different functional termini is of enormous interest for a variety 

of applications, such as surface modification or for the PEGyla-

tion of proteins and drugs.

[3]

 At present, there are two major 

pathways to synthesize 

α,ω-heterobifunctional PEG.

[4]

 The first 

is the partial functionalization of the hydroxyl end groups of 

PEG diols. In a subsequent step, the demanding separation of 

the heterobifunctional PEG from the statistical reaction mixture 

Macromol. Rapid Commun. 2019, 1900020

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