. Author manuscript; available in PMC: 2013 Sep 7.

Published in final edited form as: J Org Chem. 2012 Aug 14;77(17):7555–7563. doi: 10.1021/jo3012418

Table 1.

Fe-catalyzed cycloaddition of diynes and cyanamides

5 mol % FeCl₂, 10 mol % L2, 10 mol % Zn dust, diyne (0.4 M), cyanamide (0.48 M), benzene, 70 °C.

3 h slow addition of diyne unless otherwise noted.

TS = p-toluenesulfonyl.

TMS = trimethylsilyl.

5 h slow addition of substrate.

10 mol % FeCl₂, 20 mol % L2, 20 mol % Zn dust.