# Predicting major product of a reaction with nitrous acid

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For the above reaction I am asked to predict $\ce{X}$, the major product.

Of the options given, I thought product (1) would be correct, seeing as how it has the most stable intermediate cation (tertiary) and a highly substituted double bond.

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The answer however states that product (2) is the major product.

I can't understand why the second product would be favored over the first. There's no obvious stabilizing factor here in product (2).

• Oxonium cations are more stable than tertiary. – Mithoron May 4 '16 at 23:15
• Isn't a secondary carbocation the intermediate and not an oxonium ion for product 2?I mean, after N2 is eliminated and a hydride transer occurs from the carbonyl carbon to the carbocation, isnt a secondary carbocation formed next to electronegative oxygen? – Daipayan Mukherjee May 4 '16 at 23:35
• ...Which is a protonated carbonyl - oxonium cation. Somehow this powerful mesomeric stabilisation is often omitted – Mithoron May 4 '16 at 23:43
• (2) cannot be the major product as of the images you are supplying now unless a carbon source is added. The carbon atoms don’t add up. – Jan May 5 '16 at 12:05