A. Mack et al., Organophosphorus compounds; 140: Synthesis of new diphosphapolycycles froma tricyclic zirconocene-phosphaalkyne dimer complex, SYNTHESIS-S, (4), 1999, pp. 639-643
The tricyclic zirconocene-phosphaalkyne dimer complex 1 reacts with diethyl
mesoxalate (5) or tetracyanoethene (7) through Cp2Zr-displacement to furni
sh the novel oxadiphosphatricyclohexane 6 or the diphosphatricyclohexane 8,
respectively. In contrast, treatment of 1 with indanetrione (9) results in
the formation of the dioxadiphosphatricyclooctene 10, which has been chara
cterized by X-ray structure analysis.