Vinicius Caliman, Peter B. Hitchcock and John F. Nixon
In the nickel(II) complex [Ni(η5-P3C2But2 )(η2-P3C2But2 CH(SiMe3)2Me}] the triphosphacyclopentenyl ring P3C2But2CH(SiMe3) 2Me is unexpectedly coordinated to the metal exclusively via the two adjacent saturated ring phosphorus atoms, rather than via the 2-phosphaallyl fragment.