Hydrochloric Acid → HCID 54371518, compound

Participants

Reaction Steps

Ten ml of 5% KOH is added to 400 mg (1.00 mmole) of 3',5-dihydroxy-4'-methoxy-7-bromoethoxy-flavanone giving a bright yellow solution which is stirred under argon at ambient temperature for 2 hours. The reaction mixture is then poured into 100 ml of water, acidified with 10% HCl, and extracted immediately with ethyl acetate (2 × 25 ml). The combined extracts are washed with dilute NaHCO3 (1 × 25ml), dried over MgSO4 and concentrated yielding 0.51 g of a partially crystalline orange oil. Tlc (silica gel F-254, CH2Cl2 --CH3OH 95:5), indicates the reaction to have proceeded nearly quantitatively showing only the product (Rf =0.28) and a barely observable spot for starting material (Rf =0.73). Preparative tlc on silica gel PF-254, eluting with CH2Cl2 --CH3OH 95:5, yielded 302 mg (75%) of the chalcone as a yellow solid. Recrystallization from hexaneethyl acetate gives orange clusters having mp 158°-162°C and spectra consistent with material 7b.

Provenance & Evidence