Iodine → Methyl 3-oxovalerate

Participants

Reaction Steps

A mixture of methyl 3-oxo-4-(prop-2-ynyloxy)butyrate (2) (220 mg, 1.29 mmol), 4-phenylbenzaldehyde (247 mg, 1.29 mmol), dimedone (183 mg, 1.29 mmol), ammonium acetate (103 mg, 1.29 mmol), I2 (98 mg, 0.39 mmol), and ethanol (15 drops) is stirred under argon for 17 h, quenched with 5% Na2S2O3 (30 mL), and extracted with ethyl acetate (50 mL and 30 mL). The extract is washed (5% Na2S2O3, H2O, and brine), and dried. After solvent removal at reduced pressure, the residue is crystallized (ethanol) to give 190 mg (32%) of 3 (BI-3036) as a cream solid, mp 204-205° C. IR 3370, 2949, 1691, 1638, 1469, 1216 cm−1; NMR (CDCl3) δ 0.99 (s, 3H, CH3), 1.12 (s, 3H, CH3), 2.19-2.48 (m, 4H, COCH2, CH2), 2.56 (t, J=2.4 Hz, 1H, CH≡CCH2), 3.67 (s, 3H, OCH3), 4.34 (d, J=2.4 Hz, 2H, CH≡CCH2), 4.86-4.98 (m, 2H, CH2O), 5.14 (s, 1H, CH), 7.15 (bs, 1H, NH), 7.30-7.60 ppm (m, 9H, 4-BiphenylH).

Provenance & Evidence