Hydrochloric Acid → (+)-trans-3-Formyl-4-phenylcyclopentan-1-one

Participants

Reaction Conditions

Reaction Steps

To a solution of oxalyl chloride (1.15 mL, 13.1 mmol) in methylene chloride (30 mL) at −70° C. was added dropwise DMSO (1.87 mL, 26.3 mmol). After 15 min, a solution of (+−)-trans-1-hydroxymethyl-4oxo-2-phenylcyclopentane from Step C (1.0 g, 5.26 mmol) in methylene chloride (10 mL) was added. The reaction was stirred at −70° C. for 1.5 h and then DIPEA (9.25 mL, 53 mmol) in methylene chloride (10 mL) was added dropwise over 5 min. After a further 10 min, the mixture was allowed to warm to rt for 1 h and then diluted with methylene chloride and poured into dilute aq. HCl. The layers were separated. The aq. layer was reextracted with a second portion of methylene chloride and the organic layers were each washed with brine, dried over sodium sulfate, combined and concentrated in vacuo. The residue was purified by FC (30% ethyl acetate in hexanes) to give the title product (0.9 g) after vacuum drying.

Provenance & Evidence