Triphenylphosphine → HCID 67170697, compound

Participants

Reaction Conditions

Reaction Steps

Nitrogen was bubbled to a solution of 2-(3-phenyl-4-(trifluoromethyl)isoxazol-5-yl)-4,5-dihydronaphtho[2,1-d]oxazol-7-ol (Preparation 43C, 0.021 ml, 0.169 mmol) and (R)-(−)-2,2-dimethyl-1,3-dioxolane-4-methanol (0.021 ml, 0.169 mmol) in THF (2.5 ml) at room temperature for two min. To this mixture was added triphenylphosphine (0.044 g, 0.169 mmol) in one portion. Nitrogen was bubbled for two more minutes followed by the addition of diethyl azodicarboxylate (0.027 ml, 0.169 mmol) dropwise. The reaction vessel was immersed in a preheated oil bath held at 65° C., heated for 3 h., cooled, and concentrated under reduced pressure. The residue was extracted with ether and washed with water. The aqueous layer was re-extracted with ether and the combined organic layers were washed with brine, dried over magnesium sulfate, concentrated, and dried in vacuo. The residue was taken in 2 ml of acetic acid, cooled to 0° C. and treated with 1 ml 1N HCl. The reaction mixture was stirred at 0° C. for 30 min., concentrated under reduced pressure, and purified by silica gel column chromatography using hexane/ethyl acetate (0 to 30%) to yield (S)-3-(2-(3-phenyl-4-(trifluoromethyl)isoxazol-5-yl)-4,5-dihydronaphtho[2,1-d]oxazol-7-yloxy)propane-1,2-diol (4.3 mg, 8.92 μmol, 11.84% yield) as a clear oil. The compound had an HPLC retention time of 9.39 min (Condition: Column: Sunfire C18 3.5 um, 3.0×150 mm; (15 min); solvent A: 95/5 water/MeCN with 0.05% TFA; solvent B: 5/95 water/MeCN with 0.05% TFA; Start % B=10 to Final % B=100; Wavelength=220 nm). LC/MS M+1=473.27. 1H NMR (400 MHz, DMSO-d6) δ ppm 7.58-7.68 (5H, m), 7.45 (1H, d, J=8.36 Hz), 7.02 (1H, d, J=2.42 Hz), 6.94 (1H, dd, J=8.36, 2.42 Hz), 4.99 (1H, d, J=5.06 Hz), 4.70 (1H, t, J=5.61 Hz), 4.02-4.09 (1H, m), 3.88-3.95 (1H, m), 3.74-3.84 (1H, m), 3.42-3.50 (2H, m), 3.14 (2H, t, J=7.92 Hz), 2.90-3.00 (2H, m).

Provenance & Evidence