Iodine → 7-[2-[4-(Methylthio)phenyl]ethoxy]-2-heptanone

Participants

Reaction Steps

The product of state (i) (5.00 g) in ER (7.0 ml) was added dropwise to magnesium turnings (0.384 g) with one crystal of iodine at room temperature under nitrogen with stirring. The stirred mixture was heated to reflux for 3 h under nitrogen and the solution of Grignard reagent was added slowly to a stirred solution of acetic anhydride (2.86 g) in ER (70 ml) over a period of 1 h maintaining the temperature between -60° and -70°. After a further 2 h at -60° to -70°, the reaction mixture was allowed to warm to -10° and treated with a saturated aqueous ammonium chloride solution (20 ml). The ER layer was separated and the aqueous phase was extracted with ER (3×40 ml). The combined extracts were washed with 2N sodium hydroxide (30 ml) and brine (30 ml). The washings were extracted with ER (3×40 ml) and these extracts, combined with the previous extracts were dried and evaporated. The residual oil (3.73 g) was purified by FCC eluting with ER-H (1:14→1:7) followed by ER-CX (1:7 to give the title compound (2.17 g).

Provenance & Evidence