Quinol, diacetate

A number of o-quinol diacetates have been prepared and they rearrange smoothly to triacetoxyben-zenes o — o migration is preferred unless the latter position is blocked or sterically crowded, when acetoxy shift is directed to another aryl site. The range of possibilities is indicated by the conversions of the o-quinol diacetates (131)-(134) to the 1,2,3- or 1,2,4-triacetoxybenzenes (135)-(138), in 56-90% yields. 

Phenols with a free ortho position can also give rise to ortfeo-quinone diacetates such as 39a and 41b, in addition to or instead of ortfeo-quinol acetates such as 41a [1, 6]. Phenols bearing a 2-methoxy group are particularly prone to regioselective Wessely oxidation to give 6-... 

The quinone monoketals 9 and para-quinol ethers 10 mentioned above (Section n.A.l) can be obtained by anodic oxidation of the corresponding O-protected phenols 103 ° (equation 41) or upon oxidation of substituted phenols 104 with one equivalent of phenylrodonium diacetate (PIDA) at an ambient temperature (equation 42). 

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