You’re somewhere quiet…there’s people. It’s a solemn occasion. A wedding. No! It’s a minute’s silence for someone who’s died. Ok, a minute’s silence ticking away. The Giggle Loop begins. Suddenly, out of nowhere, this thought comes into your head…

Coupling diazo compounds with copper bronze (ultra fine copper powder). It exactly looks like glitter powder in the flask. 

Even through it was a heterogeneous reaction (the reaction took only place at the surface of the copper) a relatively high percent of the desired product formed. Good point: the side product could be removed easily via distillation, so this was a quite easy method for producing a compound. Copper and other transition metals are often used as catalyst for coupling reactions, the most popular is palladium, it is good for everything.