Ritter reaction

Schematic of the Ritter reaction. Reagents: nitrile, carbocation precursor, strong acid, water. Product: amide.

The Ritter reaction is an organic reaction used to convert a nitrile and a carbocation precursor (such as a substituted olefin or tertiary alcohol) to an amide using a strong acid and water. The mechanism begins with the formation of the carbocation from the reaction of the acid with the carbocation precursor. The nitrile then attacks the carbocation to form a nitrilium ion. Water hydrolysis and a series of proton transfer steps then yield the final amide product.[1][2]

Mechanism

Mechanism of the Ritter reaction. Both starting materials converge to the same carbocation intermediate. E1.

References:

1.
Ritter, J. J.; Minieri, P. P. J. Am. Chem. Soc. 1948, 70, 4045–4048.
2.
Ritter, J. J.; Kalish, J. J. Am. Chem. Soc. 1948, 70, 4048–4050.