Hydrochloric Acid → HCID 57803545, compound

Participants

Reaction Steps

5-Ethyl-6-hydroxy-7,8-dimethylspiro[chromene-2,1′-cyclobutan]-4(3H)-one O-methyloxime was dissolved in 10 mL of THF. To this solution at 0° C. was added BH3/pyrine complex (2.27 mL). Subsequently, a solution of 9 mL of HCl in dioxane (4.0 M) was added over a period of 1 hour. The reaction mixture was allowed to stir overnight. The mixture was extracted with ethyl acetate and washed with saturated NaHCO3. After evaporation of the solvents, the residue was purified by flash chromatography eluted with 5-8% ethyl acetate in hexane to give 136.4 mg of the product 5-ethyl-4-(methoxyamino)-7,8-dimethyl-3,4-dihydrospiro[chromene-2,1′-cyclobutan]-6-ol. 1H-NMR (300 MHz, CDCl3) δ=4.40 (b, 1H), 4.30 (m; 1H), 3.66 (s, 3H), 2.19 (s, 3H), 2.17 (s, 3H), 2.70-1.60 (m, 6H), 1.25 (t, 3H) ppm. 13C-NMR (75 MHz, CDCl3) δ=146.3, 145.2, 126.1, 124.1, 123.4, 114.1, 76.8, 61.8, 52.4, 36.0, 35.0, 32.9, 19.2, 14.9, 13.9, 13.4, 12.4 ppm. MS: (m/z)=245.1 (M−NH2OMe+).

Provenance & Evidence