Bucherer-Bergs Reaction

A multi-component reaction between a ketone, potassium cyanide and ammonium carbonate, which leads to the formation of hydantoins.

A pre-formed cyanohydrin can react with ammonium carbonate to give the same product:

---

Mechanism of the Bucherer-Bergs Reaction

The Bucherer-Bergs Reaction is equivalent to the Strecker Synthesis with "additional CO₂". Hydantoins may be opened to yield N-carbamoylamino acids which form amino acids by treatment with acid or with a suitable enzyme:

Recent Literature

Continuous Synthesis of Hydantoins: Intensifying the Bucherer-Bergs Reaction
J. L. Monteiro, B. Pieber, A. G. Corrêa, C. O. Kappe, Synlett, 2016, 27, 80-82.

Spiro Hydantoin Aldose Reductase Inhibitors Derived from 8-Aza-4-chromanones
R. Sarges, S. W. Goldstein, W. M. Welch, J. Med. Chem., 1990, 33, 1859-1865.

Modified Bucherer-Bergs Reaction for the One-Pot Synthesis of 5,5′-Disubstituted Hydantoins from Nitriles and Organometallic Reagents
C. Montagne, M. Shipman, Synlett, 2006, 2203-2206.