[1] The method relies on efficiency of bimolecular reactions with reagents to produce a more easily characterize trapped product.
A famous example is the detection of cyclobutadiene released upon oxidation of cyclobutadieneiron tricarbonyl.
Its fleeting existence is inferred by the controlled degradation of certain niobium complexes in the presence of trapping agents.
Again, a Diels-Alder strategy is employed in the trapping:[3] Another classic but elusive family of targets are silylenes, analogues of carbenes.
It was proposed that dechlorination of dimethyldichlorosilane generates dimethylsilylene:[4] This inference is supported by conducting the dechlorination in the presence of trimethylsilane, the trapped product being pentamethyldisilane: Not that the trapping agent does not react with dimethyldichlorosilane or potassium metal.