Water → 5-(2,3-Difluorophenyl)-2-hydroxycycloheptanone

Participants

Reaction Conditions

Reaction Steps

Ref. Plietker, B. J. Org. Chem. 2004, 69, 8287-8296. In a 500 mL round-bottomed flask (t=g) was added sodium bicarbonate (827 mg, 9.84 mmol) with a stirring bar. Ruthenium(III) chloride (8.17 mg, 0.039 mmol) was added (aqueous solution was used in the ref but it was difficult to completely dissolve). To the solids was added water (3.94 mL), EtOAc (20 ml), and MeCN (20 ml) to afford a brown suspension. Oxone (1.21E+04 mg, 19.69 mmol) was added in one portion, resulting in the formation of a bright yellow suspension. The mixture was cooled to −20° C. (Z)-5-(2,3-difluorophenyl)cyclohept-1-ene (820 mg, 3.94 mmol) was added (with 7.2 ml 1/1 EtOAc/MeCN wash). The color instantly turned to slightly tan. The reaction was stirred at −20 ˜−15° C. for 1.5 hours. TLC showed no reaction. Warmed up to 0° C. for 10 minutes, but by TLC the reaction didn't improve much. It was warmed up to room temperature for 15-20 minutes. TLC showed disappearing of one major less polar spot (a minor one remained) and appearance of a more polar, slightly uv-active spot. The solids were filtered and washed with EtOAc. The organic solution was washed with aqueous NaHSO3 solution. The organic layer was dried with Na2SO4 and concentrated to a colorless oil. It was purified by FCC up to 5% MeOH/CH2Cl2. The more polar peak/peaks were pooled and concentrated to a colorless oil (169 mg, 18%). It was directly carried onto the next protection reaction.

Provenance & Evidence