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Magnesium turnings (1.45 g, 59.5 mmol) were weighed into a flask which was then flame-dried under vacuum. An argon atmosphere was introduced, and anhydrous THF (30 mL) and dibromoethane (approx. 0.1 mL) were added. The mixture was stirred at room temperature. Approximately 25 mL of a solution of 22 (21.1 g, 49.6 mmol) in anhydrous THF (120 mL) was added via cannula. Within 10 min, the solution became dark yellow-brown. The remainder of the solution of 22 was then added via cannula, and the entire reaction solution was heated at reflux for 2 h. The solution was allowed to cool to room temperature, and p-formaldehyde (2.98 g, 99.2 mmol) was added. The reaction mixture was stirred at room temperature for 19 h and then poured into a separatory funnel containing saturated ammonium chloride solution. The aqueous mixture was extracted twice with diethyl ether. The organic layers were combined, washed with saturated sodium chloride solution, dried over anhydrous magnesium sulfate, filtered, and concentrated to give 19.1 g of a clear, yellow liquid. Purification by column chromatography (10:1 ratio silica gel/crude product; gradient elution with 10% to 30% ethyl acetate/hexanes) provided 11.9 g (64%) of 23 as a pale yellow oil. 1H NMR (300 MHz, CDCl3) δ7.69-7.73 (m, 4H, ArH), 7.25-7.46 (m, 10 H, ArH), 4.79 (s, 2H, CH2OSi), 4.68 (s, 2H, CH2OH), and 1.11 (s, 9H, SiC(CH3)3); 13C NMR (75 MHz, CDCl3) δ141.32, 140.67, 135.48, 133.35, 129.61, 128.41, 127.62, 125.46, 125.29, 124.54, 65.32 (CH2OSi, CH2OH), 26.75 (SiC(CH3)3), and 19.22 (SiC(CH3)3); IR (film) 3340 (br, OH), 2940, 2860, 1475, 1430, 1150, and 1110 cm-1 ; MS (FAB) m/e 399 (M+Na)+.

1. customwhich was then flame-dried under vacuum
2. additionAn argon atmosphere was introduced
3. additionanhydrous THF (30 mL) and dibromoethane (approx. 0.1 mL) were added
4. temperaturethe entire reaction solution was heated
5. temperatureat reflux for 2 h
6. temperatureto cool to room temperature
7. stirringThe reaction mixture was stirred at room temperature for 19 h
8. additionpoured into a separatory funnel
9. extractionThe aqueous mixture was extracted twice with diethyl ether
10. washwashed with saturated sodium chloride solution
11. dry with materialdried over anhydrous magnesium sulfate
12. filtrationfiltered
13. concentrationconcentrated
14. customto give 19.1 g of a clear, yellow liquid
15. customPurification
16. washby column chromatography (10:1 ratio silica gel/crude product; gradient elution with 10% to 30% ethyl acetate/hexanes)