Categories: C-N Bond Formation > Enamines

Synthesis of β-enamino esters and amides

Recent Literature

β-Keto esters efficiently react with a variety of amines in the presence of 0.1 equivalents of acetic acid as an inexpensive and environmentally benign catalyst without any solvents under ultrasound to give good yields of the corresponding β-enamino esters.
C. A. Brandt, A. C. M. P. da Silva, C. G. Pancote, C. L. Brito, M. A. B. da Silveira, Synthesis, 2004, 1557-1558.

The use of a planetary ball mill enables a solvent-free method for the addition of amines to dialkylacetylendicarboxylates or alkylpropiolates. Conversion of educts was quantitative within five minutes without use of any catalyst or base. Beside the E-/Z-isomers, no side products were formed.
R. Thorwirth, A. Stolle, Synlett, 2011, 2200-2202.

A highly regioselective hydroamination of unsymmetrical electron-poor and electron-rich alkynes with anilines is catalyzed by Au(I) under mild conditions. In addition, applications toward indole syntheses are presented including an example of a one-pot synthesis from a nonfunctionalized aniline.
S. Kramer, K. Dooleweerdt, A. T. Lindhardt, M. Rottländer, T. Skrydstrup, Org. Lett., 2009, 11, 4208-4211.