Diethylaluminum chloride → (1s,3r,5s)-3-{[Tert-butyl(dimethyl)silyl]oxy}-2-methylene-5-[(triethylsilyl)oxy]cyclohexanol

Beteiligte Stoffe

Reaktionsschritte

Tetramethylpiperidine (9.66 g, 67.7 mmol) was dissolved in 76 mL of benzene and cooled below 0° C. n-Butyllithium (2.5 M in hexane, 27.5 mL, 68.8 mmol) was added to the benzene solution below 2.5° C. The resulting solution was stirred below 0° C. Et2AlCl (1.8 M in toluene, 39 mL, 70.2 mmol) was added to the reaction below 3° C. followed by a rinse of 5.0 mL of benzene. The resulting solution was stirred at below 0° C. for 30 minutes. The compound of Example 16E (6.36 g, 17.1 mmol) dissolved in 25 mL of benzene was added to the reaction solution at below 1° C. over 10 minutes. 5.0 mL of Benzene was used as a rinse. The reaction was stirred at below 0° C. for 2.7 hours. The reaction mixture was quenched into 441 g of 17.2 wt % NH4Cl solution (cooled to below 5° C.). 104 g of 10 wt % HCl solution was slowly added to the mixture, and pH was adjusted to 2.0. The layers were separated and the aqueous layer was extracted four times with 100 mL of ethyl acetate. The combined organic layers were washed three times with 100 mL of water, then 100 mL of 7.8 wt % NaHCO3, and 100 mL of brine, and then dried over MgSO4. Filtration and concentration in vacuo yielded the title compound (6.13 g, 96%).

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