Solid Phase Stepwise Synthesis of Polyethylene Glycols. Issue 60 (6th October 2017)

• Record Type: Journal Article
• Authors: Khanal, Ashok; Fang, Shiyue
• Is Part Of: Chemistry. Volume 23:Issue 60(2017)
• Page Start: 15133
• Page End: 15142
• Publication Date: 2017-10-06
• Subjects: mass spectrometry -- monodisperse -- polyethylene glycol -- solid-phase synthesis -- synthetic methods; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201703004
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: Polyethylene glycol (PEG) and derivatives with eight and twelve ethylene glycol units were synthesized by stepwise addition of tetraethylene glycol monomers on a polystyrene solid support. The monomer contains a tosyl group at one end and a dimethoxytrityl group at the other. The Wang resin, which contains the 4‐benzyloxy benzyl alcohol function, was used as the support. The synthetic cycle consists of deprotonation, Williamson ether formation (coupling), and detritylation. Cleavage of PEGs from solid support was achieved with trifluoroacetic acid. The synthesis including monomer synthesis was entirely chromatography‐free. PEG products including those with different functionalities at the two termini were obtained in high yields. The products were analyzed with ESI and MALDI‐TOF MS and were found close to monodispersity. Abstract : Pure PEGs and derivatives are readily accessible via stepwise addition of monomers on a polystyrene support. The entire synthesis including monomer synthesis is chromatography‐free. Reactions on solid support are quantitative. The depolymerization side reaction can be avoided or kept at minimum.