[wutkung]

Hi there,

i have a question about the reaction of hydroxylamine and ketones or aldehydes. THe question is that .

Experimentally, the rate of this reaction is so slow when the solution is more acidic than pH2 or more basic than pH7 ... but the reaction goes fastest right around pH4 .. why is that?

I looked at the mechanism of this reaction and found that it is good in acidic solution because when nitrogen (nucleophile) attacks the carbonyl carbon, the double bond between C and O will be in the form of electron pair of oxygen; therefore, forms a bond with H+ (in acidic solution) and later, form water.

What i don't understand is why doesn't this reaction do the same with acidic solution at pH~1 , why was the rate of formation so low ??!! ..

please help me     >_<

[ksr985]

in very acidic media, the hydroxlyamine will react with the acid to give the salt, and the electron pair on the N will be lost.It will no longer be able to function as a carbon attacking nucleophile.