The reaction of (eta(5)-cyclopentadienyl)(1,2-benzenedithiolato)cobalt(III) (1) in quadricyclane (Q) at 90-degrees-C gives 1:1 adducts of 1 and Q. The main adduct (40% yield) has a unique structure, in which the 5- and 7-positions of norbornene are bonded to Co and S of 1. A mechanism of the formation of the adduct (by the use of deuterium-labeled Q), including a skeletal rearrangement of Q, is proposed.