Novel Syntheses of Decacyclene by Deoxygenating Cyclotrimerisation of Acenaphthenequinone with Zero-valent Titanium or Phosphorus Pentasulfide

Article abstract of DOI:10.1055/s-1997-3209

Decacyclene (2) was obtained in 15-21% yield by reaction of acenaphthenequinone (6) with bis(η⁶-biphenyl)titanium(0) (9) in toluene or diglyme at 110°C and in 18% yield by reaction of 6 with phosphorus pentasulfide in boiling toluene. The new reactions are used to attempt the conversion of 3,8-dibromoacenaphthenequinone (7) to 3,4,9,10,15,16-hexabromodecacyclene (3) which is considered to serve as a suitable precursor for the bowl-shaped polycyclic aromatic hydrocarbon C ₃₆H₁₂ (1).