Solvent and Reagent Accessibility within Oligo(ethylene glycol) Ether [PEG] Cross-Linked Polystyrene Beads

• Published in: Journal of organic chemistry Vol. 63; no. 15; pp. 5094 - 5099
• Main Authors: Wilson, Mark E, Paech, Kolja, Zhou, Wen-Jing, Kurth, Mark J
• Format: Journal Article
• Language: English
• Published: WASHINGTON American Chemical Society 24.07.1998; Amer Chemical Soc
• Subjects: Chemistry; Chemistry, Organic; Physical Sciences; Science & Technology; POLYMER NETWORKS; RESIN; SOLID SUPPORTS; CHEMISTRY; STYRENE DIVINYLBENZENE COPOLYMERS; DIFFUSION; PHASE PEPTIDE-SYNTHESIS; FLUORESCENCE PROBES; CATALYSTS; MOLECULES
• ISSN: 0022-3263; 1520-6904
• DOI: 10.1021/jo980285m

α,ω-Bis-4(vinylbenzyl) ethers of mono-, di-, tetra-, and hexa(ethylene glycol) were used as cross-linkers in polystyrene beads to examine the influence of glycol tether length and % incorporation upon polymer swelling and reagent diffusion. Swelling of 2, 10, and 20% cross-linked poly{styrene-co-[oligo(ethylene glycol) bis(4-vinylbenzyl)ether]} (PS−PEG) beads was determined to be higher or comparable to 2% cross-linked poly[styrene-co-divinylbenzene] (2% PS−DVB) beads. Fluorescence quenching of polymer-bound dansyl groups by Et3O·BF4 indicated that the most rapid intraresin diffusion of this electrophilic reagent occurred in toluene. PS−PEG beads exhibited faster quenching than 2% PS−DVB in poor swelling solvents but were slower to quench than 2% PS−DVB in toluene.