Chloride → HCID 11001420, compound

Participants

Reaction Steps

To a mixture of 1.34 g. of dimethylchloroformimium chloride and 12 ml of chlorobenzene were added 2.92 g of (± )-6-acetoxy-2,5,7,8-tetramethylchroman-2-carboxylic acid. The resulting solution was heated at 110° under N2 for 40 min and stripped of solvent to give (±) 6-acetoxy-2,5,7,8 tetramethylchroman-2-carboxylic acid chloride as a light yellow, very viscous gum. To a mixture of 2.89 mmoles of this material in 4 ml of acetone was added 0.43 ml of triethylamine and 90 mg of 10% palladium on carbon catalyst. The mixture was hydrogenated at atmospheric pressure and room temperature. Uptake ceased after 1.0 hr. The suspension was filtered and the filtrate was stripped of solvent, taken up in ether, washed with saturated aqueous sodium bicarbonate solution, 2N aqueous HCl, and brine, dried over sodium sulfate and stripped of solvent. The residue was chromatographed on silica gel with 8:2 parts by volume benzene-ethyl acetate and then crystallized from 30°-60° petroleum ether to give (±)-6-acetoxy-2,5,7,8-tetramethylchroman-2-carboxaldehyde as a white solid, m.p. 92.5°-96°.

Provenance & Evidence