Yield:876147-52-3 97%

Reaction Conditions:

with triphenylphosphine;diethylazodicarboxylate in tetrahydrofuran;toluene at 20; for 4.08333 h;

Steps:

15.C1

Triphenylphosphine (506 mg, 1.87 mmol) and phthalimide (275 mg, 1.87 mmol) were added to 4- (tert-butoxycarbonyl) morpholin-2-yl methanol (340 mg, 1.56 mmol) in tetrahydrofuran (3 mL). The mixture was stirred at room temperature for 5 min, followed by addition of a 40% diethyl azodicarboxylate/toluene solution (1.06 mL, 2.34 mmol) and stirring at room temperature for 4 hours. Subsequently, ethyl acetate was added and the mixture was washed sequentially with tap water and brine. The mixture was then dried over magnesium sulfate and the solvent was evaporated. Purification of the residue by silica gel column chromatography (hexane: ethyl acetate = 10:1 -> 3:1) gave 524 mg (97%) of the desired compound as a colorless powder. ¹H NMR (400 MHz, CDCl₃) δ 1.46 (9H, s), 2.70-2.84 (1H, m), 2.93-3.05 (1H, m), 3.45 (1H, td, J = 11.6, 3.1 Hz), 3.67 (1H, dd, J = 13.4, 4.9 Hz), 3.72-3.79 (2H, m), 3.86-4.04 (3H, m), 7.72-7.74 (2H, m), 7.86-7.88 (2H, m).

References:

EP1780210,2007,A1 Location in patent:Page/Page column 56