2-METHOXY-4'-METHYLBENZOPHENONE synthesis

Yield:28137-36-2 28%

Reaction Conditions:

Stage #1: 2-Methoxybenzoyl chloride;toluene;aluminum (III) chloride at 0 - 20;Friedel-Crafts Acylation;
Stage #2: with water in toluene;

Steps:

7.1.1

Example 7.General Procedure for the Preparation of Benzoylbenzyl BromidesBenzoylbenzyl bromides were prepared in 3 or 4 steps using toluene and the appropriate methoxybenzoyl chloride. Friedel-Crafts acylation was followed by demethylation of the methoxy function, then by O-alkylation. The aromatic methyl was then free-radical brominated.Friedel-Crafts AcylationTo a solution of aluminium chloride (1.1eq) in toluene (10eq) at 0° C. was added the appropriate acyl chloride (1eq) drop by drop. The reaction mixture was stirred to room temperature for 12 hours. The reaction mixture was then slowly hydrolysed by addition of water, and then extracted with ethyl acetate. The combined organic layers were dried over magnesium sulfate, and concentrated under reduced pressure. The residue was chromatographed over silica gel.7.1.1 (2-methoxyphenyl)(p-tolyl)methanone Prepared following the Friedel-Crafts reaction previously described using toluene and 2-methoxybenzoyl chloride. The product was chromatographed over silica gel (eluent cyclohexane/ethyl acetate 95/5). The product was obtained as a colorless oil. Yield: 28% Rf (cyclohexane/dichloromethane 9/1): 0.32 IR: νCO: 1661 cm^-1 NMR ¹H (CDCl₃): 2.50 (s, 3H); 3.75 (s, 3H); 6.97-7.09 (m, 2H); 7.22-7.26 (d, 2H, J=8.2 Hz); 7.32-7.38 (dd, 1H, J=7.6 Hz, J=1.4 Hz);); 7.42-7.52 (td, 1H, J=8.5 Hz, J=1.4 Hz); 7.71-7.78 (d, 2H, J=7.9 Hz).

References:

US2010/4159,2010,A1 Location in patent:Page/Page column 51-52