3.5- Dimethoxy-2-hydroxy acetophenone

The rearrangement of aryl and naphthyl acetates has been reported to be catalyzed by Bi(0Tf)3xH20 (Scheme 9) [68, 69]. As previously reported, only ortho-Fries products (l-hydroxy-2-acylaromatics) were produced from substrates for which ortho acylation was possible. In the case of 2,6-dimethoxyphenyl acetate, only the 3,5-dimethoxy-2-hydroxy acetophenone was produced, indicating that in this case the mechanism involves an intermolecular acyl-group transfer. As in other reactions, the nature of the true catalyst is still unclear since triflic acid also catalyzes this reaction. 

The Effect of Initiator Concentration on the Rate of Polymerization. BME, 2,2-dimethoxy-2-phenyl acetophenone, 2-hydroxy-2,2-dimethyl acetophenone and Darocur-3331 (its structure is not known) were chosen for further evaluation on the effect of initiator concentration on the rate of polymerization. They were chosen because they are the among the most active or the least active initiator in polymerizing HEMA. 

Hexanone, 2-heptanone, 2-octanone, 2-nonanone, 6-methyl-5-hepten-2-one, fenchone, carvone, acetophenone, 2-hydroxy-4,6-dimethoxy-5-methylacetophenone... 

Phan X.T. (1986) Photochemical a-cleavage of 2,2-dimethoxy-2-phenyl-acetophenone and 1-hydroxy-cyclohexyl-phenyl ketone photoinitiators. Effect of molecular oxygen on free radical reaction in solution. J. Radiation Curing, 13, 18-25. 

This compound is obtained by reaction of alkaline potassium persulfate on 3-bromo-2-hydroxy-4,6-dimethoxy-acetophenone [2917]. 

Also obtained by reaction of hydrobromic acid with 3-ethoxy-2-hydroxy-4,6-dimethoxy-acetophenone in acetic acid at r.t. (major compound) [3131]. 

Obtained by reaction of methyl iodide with 2-hydroxy-4,6-dimethoxy-5-(2-hydroxyethyl) acetophenone (m.p. 133-134°) in chloroform in the presence of silver oxide at r.t. overnight (25%) [3407]. 

N.B. The 3-isomer was obtained by selective glycosylation of 2-hydroxy-4,6-dimethoxy-acetophenone with 0-(2,3,4,6-tetra-0-benzyl-a-D-glucopyranosyl) trichloroacetimidate and trimethylsilyl triflate as promoter in methylene chloride first at -25°, then heating np to r.t. [3732,3733]. 

Obtained by treatment of 2-hydroxy-4,6-dimethoxy-acetophenone with an aqueous solution of potassium persulfate in 10% sodium hydroxide (58%) [4071]. 

Obtained by reaction of benzoyl chloride with 4,6-dimethoxy-2-hydroxy-3-(3-methyl-2-butenyl)-acetophenone in the presence of potassium carbonate in refluxing acetone for 6 h (90%) [4359]. 

COCH2OCH3 - Obtained on oxidation of 2-hydroxy-4, a-dimethoxy-acetophenone with potassium persulfate in aqueous sodium hydroxide at OH 30-40° for 90 min and at r.t. for 36 h [4905]... 

Also obtained by action of 40% aqueous hydrobromic acid with 2-hydroxy-4,a-dimethoxy-acetophenone in acetic acid on a boiling water bath for 3 h (22%) [4640]. 

Acetopiperone. (3, 4 -Methylenedioxy)acetophenone, 719 Acetosyringone. 4 -Hydroxy-3, 5 -dimethoxyacetophenone, 735, 798, 808, 840 Acetovanillone. 4 -Hydroxy-3 -methoxyacetophenone, 719,739, 746, 750, 781,1143 o-Acetovanillone. 2 -Hydroxy-3 -methoxyacetophenone, 775 Acetyldihydrodillapiole. 4-Acetyl-6,7-dimethoxy-5-propyl-l,3-benzodioxole, 962 Acetylhydroquinone. 2, 5 -Dihydroxyacetophenone, 673 2-Acetylhydroquinone. 2, 5 -Dihydroxyacetophenone, 689 8-Acetyl-4-methylumbelliferone. 8-Acetyl-7-hydroxy-4-methylcoumarin, 718 2-Acetylorcinol. 2 6 -Dihydroxy-4 -methylacetophenone, 111 8-Acetyl-4-phenylumbelliferone. 8-Acetyl-7-hydroxy-4-phenylcoumarin, 718... 

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