Ritter reaction

The Ritter reaction is a chemical reaction that transforms a nitrile into a N-alkyl amide using various alkylating reagents, for example, strong acid and isobutylene. [Ritter, J. J., Minieri, P. P.; "J. Am. Chem. Soc." 1948, "70", 4045.] [Ritter, J. J., Kalish, J.; "J. Am. Chem. Soc." 1948, "70", 4048.] [Krimen, L. I., Cota, D. J.; "Org. React." 1969, "17", 213-325. (Review)]

Primary [Lebedev, M. Y., Erman, M. B.; "Tetrahedron Lett." 2002, "43", 1397-1399. ( [http://dx.doi.org/doi:10.1016/S0040-4039(02)00057-6 Article] )] , secondary [Bishop, R.; In "Comp. Org. Synth."; Trost, B.M., Fleming, I.; Eds.; Pergamon Press: New York, 1992; Vol. 6, 261-300. (Review)] , tertiary [Ritter, J. J., Kalish, J.; "Organic Syntheses", Coll. Vol. 5, p.471 (1973); Vol. 44, p.44 (1964). ( [http://www.orgsyn.org/orgsyn/prep.asp?prep=cv5p0471 Article] )] , and benzylic [Parris, C. L.; "Organic Syntheses", Coll. Vol. 5, p.73 (1973); Vol. 42, p.16 (1962). ( [http://www.orgsyn.org/orgsyn/prep.asp?prep=cv5p0073 Article] )] alcohols, as well as "tert"-butyl acetate [Fernholz, H., Schmidt, H.J.; "Angew. Chem., Int. Ed. Eng.", 1969, 8, 521. ( [http://dx.doi.org/doi:10.1002/anie.196905211 Article] )] , also successfully react with nitriles in the presence of strong acids to form amides via the Ritter reaction.

Reaction mechanism

The Ritter reaction proceeds by the electrophilic addition of either the carbenium ion 2 or covalent species [Booth, B.L., Jibodu, K.O., Proenca, F.J.R.P.; "J. Chem. Soc., Perkin Trans. 1", 1983, 1067 - 1073, ( [http://dx.doi.org/doi:10.1039/P19830001067 Article] )] [Martínez, A.G., Alvarez, R.M., Vilar, E.T., Fraile, A.G., Hanack ,M., Subramanian, L. R.; "Tetrahedron Lett." 1989, "30", 581-582. ( [http://dx.doi.org/doi:10.1016/S0040-4039(00)95260-2 Article] )] to the nitrile. The resulting nitrilium ion 3 is hydrolyzed by water to the desired amide 5.

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