I was working on Husigen reaction with copper 1+ catalyst (cuso4 with sodium ascrobate) for this month. But, the result is not so well. A lot of white ppt formed. I tried to change the order of chemical addition and the speed of additon. But it does not help.

I think this reaction should be an easy reaction. But, i found this to be a very hard synthesis with an extra low yield...

I hope there could be an answer to this