Decacyclene easy synthesis from acenaphthylene upon differential scanning calorimetry

Decacyclene (C36H18) is an interesting shallow molecular propeller polycyclic aromatic hydrocarbon reproducing 60% of the C60 fullerene open cage. The synthesis of decacyclene was studied in a high-pressure crucible starting from acenaphthylene heated in a DSC (Differential Scanning Calorimeter). At 350 °C acenaphthylene is essentially polymerized into poly(acenaphthylene) with an activation energy E# = 62.6 kJ/mol and polymerization enthalpy of ΔHls = −39.0 kJ/mol. Decacyclene is formed in the high-pressure crucible above 400 °C in good yields reaching 37% by weight accompanied by acenaphthene as carrier of the hydrogen released during the dehydrotrimerization reaction of acenaphthylene. The reaction products were studied with electronic absorption spectroscopy, selective solvent extraction and HPLC analysis, FT-IR spectroscopy. Astrochemical considerations were made about decacyclene formation from acenaphthylene (the cyano-derivative of this molecule was already detected in TMC-1 cold molecular cloud) and further potential fate of decacyclene in space.