[djavko]

Hi!
Might not be for organic chemistry, but I am an organic chemist and that might be part of the reason why I need help with this.
I am trying to reduce NiO in order to make Ni(PPh3)4 in situ. That goes well both with n-BuLi and Zn as a reducing agent, but once small amount of Cu(I) is added, the reduction is completely blocked. More precisely, I don't see deep red coloration of Ni(PPh3)4. I find this bizzarre, specially since there are papers that say that Cu should enhance the reduction of NiO. Please help.