[C:1]([O:5][C:6]1[CH:11]=[CH:10][C:9]([OH:12])=[CH:8][CH:7]=1)([CH3:4])([CH3:3])[CH3:2].[O:13]([CH2:21][CH2:22]O)[Si:14]([C:17]([CH3:20])([CH3:19])[CH3:18])([CH3:16])[CH3:15].C1C=CC(P(C2C=CC=CC=2)C2C=CC=CC=2)=CC=1.CC(OC(/N=N/C(OC(C)C)=O)=O)C>C1(C)C=CC=CC=1>[C:1]([O:5][C:6]1[CH:7]=[CH:8][C:9]([O:12][CH2:22][CH2:21][O:13][Si:14]([C:17]([CH3:20])([CH3:19])[CH3:18])([CH3:16])[CH3:15])=[CH:10][CH:11]=1)([CH3:4])([CH3:2])[CH3:3]4-Tert-butoxyphenol (1 g, 6.02 mmole), 2-(t-butyldimethylsiloxy)ethanol (1.38 g, 7.83 mmole), and PPh3 (2.05 g, 7.82 mmole) were combined in toluene (30 mL) at RT. To this was added DIAD (1.52 mL, 7.82 mmole) slowly at RT. After stirring overnight the mixture was concentrated. Flash column chromatography (Biotage-SNAP-50 g SiO2, 0-10% EtOAc/hexanes) gave the title compound (1.7 g, 87%) as a clear oil. 1H NMR (400 MHz, CDCl3): δ 6.90 (d, J=8.8 Hz, 2 H); 6.80 (d, J=8.8 Hz, 2 H); 4.03-3.92 (m, 4 H); 1.30 (s, 9 H); 0.91 (s, 9 H); 0.10 (s, 6H).
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