Collision-induced dissociation evidence for charge separation and “ball-and-chain” propagation in the addition of 1-butene to C602+

The collision-induced dissociation of the adduct ions C60(C4H8) 2 (2+) and C60(C4H8) 3 (2+) formed by sequential reactions of C 60 (2+) with 1-butene has been investigated by using a selected-ion flow tube (SIFT) apparatus. Experiments at 295 ± 2 K in 0.35 ± 0.02 torr of helium indicated that C 60 (2+) adds at least five molecules of 1-butene in a sequential fashion with rates that decrease with the number of molecules added. Collision-induced dissociation experiments in which the downstream sampling nose cone of the SIFT was biased with respect to the flow tube indicated that the adduct ions C60(C4H8) 2 (2+) and C60(C4H8) 3 (2+) dissociate into C 60 (·+) and (C4H8) 2 (·+) and (C4H8) 3 (·+) , respectively. These observations provide evidence for the occurrence of charge separation in the derivatization of C60 dications and support the "ball-and-chain" mechanism first proposed by Wang et al. in 1992 for the sequential multiple addition of 1,3-butadiene to C 60 (2+) and C 70 (2+) .