Triphenylphosphine → 4-[3-[4-(1-Imidazolyl)benzyloxy]phenyl]-4-methoxy-3,4,5,6-tetrahydro-2H-pyran

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a stirred solution of 4-(1-imidazolyl)benzyl alcohol (Eur. J. Med. Chem., 1992, 27, 219) (0.87 g, 5.0 mmol), 4-(3-hydroxyphenyl)-4-methoxy-3,4,5,6-tetrahydro-2H-pyran (J. Med. Chem., 1992, 35, 2600) (1.03 g, 4.9 mmol) and triphenylphosphine (1.55 g, 5.9 mmol) in THF (30 ml) cooled to 0° C. was added dropwise a solution of diethyl azodicarboxylate (DEAD) (1.03 g, 12.0 mmol) in THF (10 ml) over 20 min under a nitrogen atmosphere. After completion of addition, the mixture was stirred at 0° C. for 30 min and allowed to warm to room temperature, and then volatiles were removed under reduced pressure. Chromatographic purification of the residue (SiO2, 230 g; gradient elution, 15% to 30% acetone in dichloromethane) provided 0.27 g of the title compound as a gum, which solidified on standing at room temperature. Fractions contaminated with triphenylphosphine oxide were combined, concentrated to dryness, solidified by triturating with diisopropyl ether and recrystallized from diisopropyl ether / ethyl acetate to provide 0.16 g of the title compound. Combined solids were further purified by recrystallization from diisopropyl ether / ethyl acetate afforded the title compound as tiny colorless needles (0.30 g, 17%).

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