The IUPAC name is methandiol. the names you have written are wrong. also read this http://en.wikipedia.org/wiki/Methanediol
Surely it is not possible.you can not find methandiol.if any carbon having two -oh group that is unstable
Abdul..what you are saying may be true in certain condition and would be wrong in many other condition. for Example "Methanediol is a product of the hydration of formaldehyde H2C=O, and predominates in water solution: the equilibrium constant being about 10E3, and a 5% by weight solution of formaldehyde in water is 80% methanediol (from wikipedia)". please contradict me with proper explanation and chemistry if i am wrong ..i will appreciate it.
Formation Of Gemdiol
Carbonyl compounds react with water to give gem diols. This reaction is catalysed by acid. The reaction is reversible reaction.
O OH
|| |
R – C – R' + HOH ? R – C – R'
Ketone |
OH
Gemdiol
Gem diols are highly unstable compounds hence equilibrium favours the backward direction. The extent to which an aldehyde or ketone is hydrated depends on the stability of gem diol.
Stability of gem diols depend on the following factors:
(i) Steric hindrance by +I group around α-carbon decreases the stability of gem diols. +I group decreases stability of gem diol and hence decreases extent of hydration.
(ii) Stability of gem diols mainly depends on the presence of –I group on α-carbon. More is the –I power of the group more will be stability of gem diols.
(iii) Intramolecular hydrogen bonding increases stability of gem diols. –I groups present on carbon having gem diol group increases strength of hydrogen bond.
More is the strength of hydrogen bond more will be the stability of gem diol.
O OH
|| |
R – C – R' + HOH ? R – C – R'
Ketone |
OH
Gemdiol
(i) Steric hindrance by +I group around α-carbon decreases the stability of gem diols. +I group decreases stability of gem diol and hence decreases extent of hydration.
Comment: Here we are talking about one of the special kind of gemdiol, where R and R' are hydrogen atoms. +I effect of two Hydrogen atom attached to the alpha carbon is much less than any other electron releasing R or R' group (Ex. CH3,C2H5 etc). In addition hydrogen atoms causing the least steric hinderence.
(ii) Stability of gem diols mainly depends on the presence of –I group on α-carbon. More is the –I power of the group more will be stability of gem diols.
I agree there is no -I group. but there is not any effective +I group either.
and I already said that methandiol is stable in aqueous solution. it is not stable by itself.
The ease of Hydration is the best for formaldehyde while it is worst for acetone. (of course if you keep removing beta hydrogen by electron withdrawing group then it will again stablize the hydrated form)
"Something is Unstable Does not mean it does does not exist and its formation not possible"
I hope you understand what i mean.
Chloral hydrate (2,2,2-trichloroethane-1,1-diol) is a good example of stabilization by -I as first mentioned in this thread by Abdul. By the way, chloral hydrate is a hypnotic drug and its possession is restricted by many governments.
two bulky groups like -OH can not remain stable when attached to same carbon atom.they give rise to >C=O by eliminating a water molecule. A labile equilibrium is established with equilibrium shifting more toward >C=o.
I never thought the answers requires lot of theory reading-thanks all-vasant
Methanediol is real--it even has its own CAS number [463-57-0]. It exists in equilibrium with formaldehyde in water solution. There are known instances where customs, OSHA, or environmental reporting regulations have been skirted by claiming that items are 'formaldehyde free' because they contain methanediol or methylene glycol.
So, yes, of course it's real--unless you're one to insist on seeing a crystal structure of it or you want to hold a chunk of it in your hand...
Methane Diol is white crystalline solid very stable at room temperature is a result of a cid catalyzed reaction of aldols
Hii, am sure of methane diols and triols like p-methane,18 diol, 3,8 diol, 2,78 triol but as a aromatic compounds not aliphatic compounds,either way these are crystalline solids.I have synthesis these from lemon eucalyptus through acid catalyzed reaction .
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