Hydrochloric Acid → HCID 18180309, compound

Participants

Reaction Steps

To 1.06 g (2.72 mmole) of [(2S)-7-amino-6-fluoro-2,3-dihydro-1,4-benzodioxin-2y]methyl 4-methylbenzenesulfonate hydrochloride was added 100 mL of concentrated hydrochloric acid. Then 0.66 g (2.68 mmole) of p-chloranil was added with sufficient ethanol to wash down the solid. The heterogeneous mixture was heated to reflux and a solution of 0.25 g (4.45 mmole) of acrolein in 10 mL of ethanol was added dropwise. Reflux was continued for an additional 1 hour. The mixture was then allowed to come to room temperature and added to ice water. The solution was made basic with 1 N NaOH and extracted with methylene chloride. The extract was dried over magnesium sulfate, filtered and concentrated to a crude brown oil in vacuum. This was column chromatographed on silica gel with 1:1 hexane/ethyl acetate and the product-containing fractions concentrated in vacuum to give 0.60 g of the (R)-enantiomer of the title compound as a yellow oil. 1H-NMR (CDCl3): doublet 8.6 δ(1 H); doublet 8.2 δ(1 H); doublet 7.75 δ(2 H); multiplet 7.4 δ(1 H); doublet 7.25 δ(2 H); doublet 7.0 δ(1 H); multiplet 4.58 δ(1 H); multiplet 4.2-4.4 δ(3 H); multiplet 4.2 δ(1 H); singlet 2.4 δ(1 H).

Provenance & Evidence