Irregularities in the Effect of Potassium Phosphate in Ynamide Synthesis
Karin Dooleweerdt, Henrik Birkedal, Thomas Ruhland and Troels Skrydstrup*
*Department of Chemistry and the Interdisciplinary Nanoscience Center, University of Aarhus, Langelandsgade 140, 8000 Aarhus C, Denmark, Email: tschem.au.dk
K. Dooleweerd, H. Birkedal, T. Ruhland, T. Skrydstrup, J. Org. Chem., 2008, 73, 9447-9450.
In copper-catalyzed direct N-alkynylation, the use of pure and anhydrous K3PO4 provides higher ynamide yields in comparison to samples contaminated with hydrates (K3PO4 · 1.5 H2O and K3PO4 · 7 H2O). With high quality K3PO4, a number of ynamides were synthesized in good yields. In addition, ynamides can undergo regioselective hydroamination with carbamates.
see article for more examples
This publication refers to a method by Richard P. Hsung. See for example:
X. Zhang, Y. Zhang, J. Huang, R. P. Hsung, K. C. M. Kurtz, J. Oppenheimer, M. E. Petersen, I. K. Sagamanova, L. Shen, M. R. Tracey, J. Org. Chem., 2006, 71, 4170-4177.
Reto Mueller, March 25, 2010