Sugar-modified silanes: precursors for silica monoliths

Michael A. Brook, Yang Chen, Kui Guo, Zheng Zhang, John D. Brennan
2004 Journal of Materials Chemistry  
Syntheses CH2=CHCH2(CH2CH2O)nCH2CH=CH2, ATPEO600: ATPEO600: To a solution of poly(ethylene glycol) (average MW 600, 6.0 g, ca.10 mmol) in THF (100 mL) at 0°C was added NaH (0.50 g, 20.8 mmol) slowly over 15 min. The mixture was allowed to warm up to room temperature and stirred for 5 h. The mixture was cooled down to 0 °C, allyl bromide (2.42 g, 20.0 mmol) was added. The mixture was warmed up to 40 °C and stirred for further 3 h. White precipitate was filtered off and washed with THF (3×10 mL).
more » ... with THF (3×10 mL). Combined filtrate and washing solution, THF was evaporated to give pale yellow crude product. The crude product was purified by chromatography (SiO 2 , 10% ethyl acetate in hexane as eluent) give allyl terminated poly(ethylene glycol), ATPEO600 as colorless oil, 6.1 g, (ca. 90% yield). 1 H NMR (200.2 MHz, CDCl3): δ 3.54-3.65 (m, 44H, PEO's OCH 2 ), 3.97 (dd, 2H, J=5.6Hz, J=1.1Hz CH 2 =CHCH 2 O), 3.98 (dd, 2H, J=5.6Hz, J=1.1Hz CH 2 =CHCH 2 O), 5.19 (m, 4H, CH 2 =CHCH 2 O), 5.88 (m, 2H, CH 2 =CHCH 2 O) ppm. 13 C NMR (50.3 MHz, CDCl 3 ): δ 69.4, 70.5 (PEO's OCH 2 ), 72.2 (CH 2
doi:10.1039/b401278j fatcat:3rx7bjxwhncmzd7yah4j5c7yf4