Geminal diol

A geminal diol (or gem-diol for short) is any organic compound having two hydroxyl functional groups (-OH) bound to the same carbon atom.

Other examples are: Geminal diols can be viewed as ketone (or aldehyde) hydrates.

[2] For conversion of hexafluoroacetone (F3C)2C=O to the diol (F3C)2C(OH)2, the constant is about 10+6, due to the electron withdrawing effect of the trifluoromethyl groups.

In some cases, such as decahydroxycyclopentane and dodecahydroxycyclohexane, the geminal diol is stable while the corresponding ketone is not.

Geminal diols can also be viewed as extreme cases of hemiacetals, formed by reaction of carbonyl compounds with water, instead of with an alcohol.