4-Methoxyphenylacetic Acid → HCID 54162773, compound

Participants

Reaction Steps

The process described in the third and fourth paragraphs of Example 1 was repeated using p-methoxyphenylacetic acid and 2-m-tolylethyl methanesulphonate as starting materials. The 3,4-dihydro-2-p-methoxyphenyl-6-methylnaphthalen-1(2H)-one thus obtained (1.33 g., m.p. 125°-126° C. after crystallisation from methanol) was added to a stirred solution of lithium diisopropylamide in tetrahydrofuran [prepared from n-butyllithium (5 ml. of a 1.5 molar solution in hexane) and a solution of diisopropylamine (0.8 g.; freshly distilled from potassium hydroxide) in tetrahydrofuran (20 ml.)] which was cooled to -20° C. under an atmosphere of argon. The mixture was stirred at -20° C. for 1 hour, methyl iodide (1.27 g.) was added and the mixture was stirred at laboratory temperature for 18 hours. Aqueous N-hydrochloric acid (50 ml.) was added and the mixture was extracted twice with diethyl ether (50 ml. each time). The combined extracts were dried and evaporated to dryness and the residue was purified by medium pressure chromatography on a silica gel column using a 12.5:1 v/v mixture of petroleum ether (b.p. 60°-80° C.) and ethyl acetate as eluent. The product was crystallised from petroleum ether (b.p. 60°-80° C.) and there was thus obtained 3,4-dihydro-2-p-methoxyphenyl-2,6-dimethylnaphthalen-1(2H)-one, m.p. 80°-82° C.

Provenance & Evidence