8-Acetyl-7-hydroxy-4-methylcoumarin

Also obtained (poor yield) by Fries rearrangement of 6,6 -bi-(7-acetoxy-4-methylcoumarin) (m.p. 327°) with aluminium chloride at 260° for 75 min, followed by heating the resulting 6,6 -bi-(8-acetyl-7-hydroxy-4-methylcoumarin) with 20% (w/v) aqueous sodium hydroxide on a steam bath for 5 h under nitrogen (<3%) [5842]. 

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... 

Alkyl phenols, e.g. cresols and xylenols, by heating with a large excess of chlorosulfonic acid (10 equivalents), are sulfonated and cyclized to the corresponding sulfonylide disulfonyl chlorides. Thus o-cresol yields the cyclized product 7 and a similar reaction was also observed with 8-acetyl-7-hydroxy-4-methylcoumarin (see Chapter 6, p 202). 

Obtained by saponification of 8-acetyl-6-bromo-7-hydroxy-4-methylcoumarin with 10% aqueous sodium hydroxide solution at reflux (64%) [1982,1983]. 

C2H5v. A. COCH3 - Preparation by degradation of 8-acetyl-6-ethyl-7-I ll hydroxy-4-methylcoumarin with refluxing 2 N... 

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