3924-44-5Relevant academic research and scientific papers
Bimolecular Formation of Radicals by H-Transfer, 2. - H-Transfer Reactions of Phenalene
Gerst, Matthias,Ruechardt, Christoph
, p. 1039 - 1046 (2007/10/02)
The uncatalysed H transfer from phenalene (7) to α-methylstyrene (2) and the selfreaction (d) of phenalene (7) are quantitative transformations in the presence of an excess of 9,10-dihydroanthracene (1) (DHA) in diphenyl ether at 200 - 250 deg C.In this system phenalene (7) is consumed only in reaction (d) because the phenalenyl radicals (9) are captured by DHA (1) to give phenalene (7) and 9,10-dihydroanthryl radicals (3).The latter disproportionate rapidly.Accordingly, phenalene (7) acts as a catalyst for the hydrogenation of α-methylstyrene (2) by DHA (1).The activation parameters of the two reactions (e) and (d) were obtained from kinetic experiments between 200 - 250 deg C.They allow the determination of the C-H bond enthalpy ΔHdiss of phenalene (7) (65.3 kcal mol-1) at the methylene position.Key Words: Hydrogen transfer / Radical formation, molecule induced / C-H bond dissociation enthalpies, determination of / Catalysis / Coal pyrolysis / Phenalene
Electrocyclic Ring Opening of the 6b,7a-Dihydro-7H-cyclopropacenaphthylene Radical Anion
Dodd, John R.,Pagni, Richard M.,Watson, Charles R.
, p. 1688 - 1692 (2007/10/02)
The Na-K alloy and electrochemical reduction of the naphthocyclopropane 6 were investigated.The radical anion of 6 was found to be very labile and could not be observed spectroscopically.In the Na-K reduction of 6, the phenalenyl radical (9) was detected as an intermediate in the reduction, and the phenalenyl anion (10) and perinaphthane (8) were found to be the products of the reduction.Evidence was obtained from polarographic and cyclic voltammetric studies that 8-10 are also formed in the electrochemical reduction of 6.A mechanism is proposed for this reduction which involves an initial electrocyclic ring opening of the cyclopropane ring in the radical anion of 6 which is followed by a 1,2-shift of hydrogen to yield the radical anion of phenalene (11).The radical anion of 11 is then further transformed into 8 and 10; the latter transformation has previously been reported.
