n-methyl pyrolidone

[praveenpaliwal]

Hellow ,

can any one tell me that this n-methyl pyrrolidone shows the keto enol tautomerism if we analyse this on RP-HPLC
Our mobile phase is ACN(0.1% H3PO4) : Water (0.1% H3PO4) .
Our main question again this can this n-methyl pyrrolidon shows keto-enol tautomerim or not

Thanks in advance

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[Mark Tracy]

NMP like most other amides strongly favors the keto form. As a secondary amide, the enol form would be a zwitterion, making it even more unfavorable.

[praveenpaliwal]

Hellow sir i agree with u but in acidic media this keto form change in enol form and eluted earlier and have +ive charged on nitrogen . Is it possible

Plz reply me

thanks

praveen

[Mark Tracy]

Amides are extremely weak bases, and to significantly protonate them, you would need conditions that are destructive both to the amide and to most HPLC columns.