Preparation by Friedel–Crafts acylation of p-nitrophe-nol with propionyl chloride in nitrobenzene in the presence of aluminium chloride (36%)
Also obtained by Fries rearrangement of p-nitrophenyl propionate (m.p. 63–64°) in nitrobenzene in the presence of aluminium chloride at 125° for 5 h (23%)
Preparation by reaction of boron trichloride with 2-methoxy-5-nitropropiophe-none in methylene chloride, first at ?78°, then at r.t. for 14 h (92%). Also obtained by nitration of o-hydroxypropiophenone (23%), in acetic acid with fuming nitric acid, first at 0°, then at 60°
Also obtained by alkaline hydrolysis of 3-methyl-6-nitrochromone (m.p. 147–148°) (85%).
