2.6- Dihydroxy-4-methoxyacetophenone

Claimed to be obtained as a minor component in the steam distillates of the resins from various species of Xanthorrhoea (X.) X. tateana F. Muell. and X. preissi (m.p. 79°) [2584], but also from X. arborea R. Br. and X. reflexa. (m.p. 79°) [2761]. Thus, this compound, the 2,6-dihydroxy-4-methoxyacetophenone has a melting point of 136-137° (see below). Two possibilities may then occur ... 

Preparation by reaction of 3,4-dihydro-27/-pyran on 2,6-dihydroxy-4-methoxyacetophenone with p-toluene-sulfonic acid in dioxane, first at 0°, then... 

Obtained by reaction of 4-bromo-2-methyl-2-butene with 2,6-dihydroxy-4-methoxyacetophenone in the presence of potassium hydroxide. 

Ozone or performic acid readily converts 106 into the aldehyde 107, which then undergoes cyclodehydration to 108 with PPA.201 Thus, 4-allyloxy-2-hydroxy-cu-methoxyacetophenone gives (Claisen) 3-allyl-2,4-dihydroxy-w-methoxyacetophenone, then (with ozone) aldehyde (109) and 4-hydroxy-5(methoxyacetyl)benzofuran (110). 

Dihydroxy-2-methoxyacetophenone from 2-hydroxy-6-methoxyacetophenone 303 2-Hydroxy-6-methoxyacetophenone (16 g) is dissolved in Jo% sodium hydroxide solution (200 ml) and cooled to 15°, at which temperature a solution of potassium persulfate (26 g) in water (500 ml) is dropped in during 4 h. The mixture is set aside at room temperature for... 

A soln. of 2,3 -dihydroxy-4 -methoxyacetophenone diacetate, acetaldehyde, and coned. HCl in glacial acetic acid heated 1.5 hrs. on a steam bath l-(3 -hydroxy-4 -methoxyphenyl) l,2-butanedione. Y 81%. H. S. Verter and G. Williamson, J. Chem. Eng. Data 13, 290 (1968). 

Also obtained by dealkylation of 2,3-dihydroxy-4-methoxyacetophenone with aluminium chloride in refluxing chlorobenzene [2406],... 

Also obtained by hydrolysis of 2,4-dihydroxy-6-methoxyacetophenone diacetate [2791],... 

Preparation by reduction of 3-formyl-2,4-dihydroxy-6-methoxyacetophenone with hydrochloric acid and amalgamated zinc in gently heated aqueous methanol (64%) [3036]. 

Preparation by partial alkylation of 2,5-dihydroxy-3-methoxyacetophenone with isopropyl snlfate in 0CH(CH3)2 alkaline medium (41%) [2848]. 

Preparation by reaction of diethyl sulfate on 2-ethoxy-3,6-dihydroxy-4-methoxyacetophenone with potassium carbonate in boiling acetone [2851]. 

Preparation by reaction of 3 -chloro-3 -meth-ylbut-l-yne with 2,4-dihydroxy-3-iodo-6-methoxyacetophenone in the presence of potassium carbonate and potassium iodide in refluxing acetone (56%) [2064],... 

Also obtained by benzylation of 2,5-dihydroxy-3,4,6-tri-methoxyacetophenone with benzyl chloride [3322]. 

Also obtained by reaction of o-(benzyloxy)benzyl alcohol with 2,4-dihydroxy-6-methoxyacetophenone in the presence of boron trifluoride etherate in dioxane (7%) [2325]. 

Also obtained from 2,4-dihydroxy-5-prenyl-6-methoxyacetophenone (multi-step reaction) [4352]. 

Obtained by reaction of dimethyl sulfate with 2,4-diethoxy-3,6-dihydroxy-a-methoxyacetophenone in the presence of potassium carbonate in refluxing acetone for 2.5 h [4993], (27%) [4867] or for 12 h [4854]. 

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... 

Calycopterin diethyl ether. 5,4 -Diethoxy-3,6J,8-tetramethoxyflavone, 1342 Calycopterin dimethyl ether. 3,5,6,7,8,4 -Hexamethoxyflavone, 1340 Calycopterol pentamethyl ether. l-(2-Hydroxy-3,4,5,6-tetramethoxyphenyl)-2-methoxy-ethanone, 1340-1341 Carvacrol. 2-Methyl-5-isopropylphenol, 1264 Casticin. 5,3 -Dihydroxy-3,6,7,4 -tetramethoxyflavone, 131 a-Chloroacetovanillone. a-Chloro-4 -hydroxy-3 -methoxyacetophenone, 1384 Chlorflavonin. 3 -Chloro-5,2 -dihydroxy-3,7,8-trimethoxyflavone, 1335 Chlorflavonin dimethyl ether. 3 -Chloro-3,5,7,8,2 -pentamethoxyflavone, 1335 Cladrastin. 7-Hydroxy-6,3, 4 -trimethoxyisoflavone, 1505 Cladrin. 7-Hydroxy-3, 4 -dimethoxyisoflavone, 1487 Creosol. 2-Methoxy-4-methylphenol, 1242... 

P-Orcacetophenone. 2 4 -Dihydroxy-6 -melhylacetophenone, 1572 y-Orcacetophenone. 2 6 -Dihydroxy-4 -methylacelophenone, 1572 Orcinol. 5-Melhyl-l,3-benzenediol, 1241,1324, 1419, 1466, 1481 Oxyayanin-A triethyl ether. 5,2, 5 -Triethoxy-3,7,4 -trimethoxyflavone, 1334 Oxyayanin-B triethyl ether. 5,6,3 -Triethoxy-3,7,4 -trimethoxyflavone, 1341 Oxyayanin-A trimethyl ether. 3,5,7,2 4, 5 -Hexamethoxyflavone, 1330 Paeonol. 2 -Hydroxy-4 -methoxyacetophenone, 1573,1577, 1622 Patuletin hexamethyl ether. 3,5,6,7,3 4 -Hexametfioxyflavone, 1337 Patuletin pentaethyl ether. 3,5,7,3 4 -Pentaethoxy-6-methoxyflavone, 1350 Penduletin dimethyl ether. 3,5,6,7,4 -Pentamethoxyflavone, 1337 O-Pentamethyldihydromelanoxetin. 3,7,8,3, 4 -Pentamethoxyflavanone, 1329... 

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