Unexpected zirconium-mediated multicomponent reactions of conjugated 1,3-butadiynes and monoynes with acyl cyanide derivatives.

Going ber(zirc): zirconium-butadiyne complexes react with acyl cyanide derivatives through diverse reaction pathways. The complexes react with two molecules of carbamoyl cyanide to form 1,4-benzodiazepin-2-one-derivatives containing azazirconacycles. Reactions with either aroyl cyanides or alkyl cyanoformates lead to azazirconacyclopentenes containing a quaternary carbon center.