4-Bromoanisole → N-(4-Methoxyphenyl)-2-azetidinone

Temperature

110 °C

An oven-dried resealable Schlenk tube was charged with CuI (6.0 mg, 0.0315 mmol, 1.0 mol %), 2-azetidinone (300 mg, 4.22 mmol), K2CO3 (850 mg, 6.15 mmol), evacuated and backfilled with argon. trans-1,2-Cyclohexanediamine (40 μL, 0.333 mmol, 11 mol %), 4-bromoanisole (0.38 mL, 3.04 mmol) and dioxane (0.50 mL) were added under argon. The Schlenk tube was sealed and the reaction mixture was stirred magnetically at 110° C. for 23 h. The resulting suspension was cooled to room temperature and filtered through a 0.5×1 cm pad of silica gel eluting with 10 mL of ethyl acetate. The filtrate was concentrated and the residue was purified by flash chromatography on silica gel (2×20 cm; hexane-ethyl acetate 1:1; 20 mL fractions). Fractions 10–22 provided 320 mg (59% yield) of the product as white crystals. 1H NMR (400 MHz, CDCl3): δ 7.35–7.29 (m, 2H), 6.91–6.86 (m, 2H), 3.81 (s, 3H), 3.60 (t, J=4.4 Hz, 2H), 3.11 (t, J=4.4 Hz, 2H).

1. customevacuated
2. customThe Schlenk tube was sealed
3. temperatureThe resulting suspension was cooled to room temperature
4. filtrationfiltered through a 0.5×1 cm pad of silica gel eluting with 10 mL of ethyl acetate
5. concentrationThe filtrate was concentrated
6. customthe residue was purified by flash chromatography on silica gel (2×20 cm; hexane-ethyl acetate 1:1; 20 mL fractions)

ORD record

ord-51f01911f24f4d3580bc0d7688803f2b

Source dataset

uspto-grants-2006_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07115784B2