55720-25-7Relevant academic research and scientific papers
Flash Vacuum Pyrolysis of Phenanthrene-3,4-dicarboxylic Anhydride and Cyclobutaphenanthrene-1,2-dione: Products of Ring Contraction, Insertion and Ring Cleavage
Adeney, Michael,Brown, Roger F. C.,Coulston, Karen J.,Eastwood, Frank W.,James, Ian W.
, p. 967 - 980 (2007/10/02)
Flash vacuum pyrolysis of phenanthrene-3,4-dicarboxylic anhydride and cyclobutaphenanthrene-1,2-dione (860-70 degree/0.02-0.04 mm) gave a pyrolysate containing 1-ethynylacenaphthylene, 3-ethynylacenaphthylene and phenanthrene.The identity of the two ethynes was confirmed by synthesis.The results are interpreted in terms of a reaction sequence involving aryne formation, ring contraction, carbene insertion and ring cleavage of a highly strained intermediate.
Kinetic Control and Locoselectivity in the Electrophilic Cleavage of Allylic Aluminum Compounds: Reactions of Acenaphthenylaluminum Reagents with Carbonyl Substrates
Eisch, John J.,Fichter, Kenneth C.
, p. 4631 - 4639 (2007/10/02)
The benzylic reagent 1-acenaphthenyldiisobutylaluminum, which is formed by the addition of diisobutylaluminum hydride to acenaphthylene, exhibits a 1H NMR spectrum at 25 deg C consistent with a C1-Al bond.At 110 deg C the carbon-aluminum bond undergoes configurational inversion, as evidenced by the magnetic equivalence of the cis and trans C2 protons.At -78 deg C this aluminum compound reacts with ketones to give, upon hydrolysis, 65-75percent of 3-(α-hydroxy-disubstituted methyl)-1,3-dihydroacenaphthylenes, which undergo acid-catalyzed isomerization to 3-(α-hydroxy-disubstituted methyl)acenaphthenes and which dissociate into acenaphthene and the ketone upon contact with Pd.On the other hand, the same reagents at 80-100 deg C lead to the formation of 75-85percent of 1-(α-hydroxy-disubstituted methyl)acenaphthenes.Similiar reactions with acyl chlorides (RCOCl, where R = Me, Et, Ph) and with Me3SiCl laed to 3-acylacenaphthenes and 1-(trimethylsilyl)acenaphthene, respectively.The stereochemically defined adduct of acenaphthylene and diisobutylaluminum deuteride, (cis-2-deuterio-1-acenaphthenyl)diisobutylaluminum diethyl etherate, is found to react with 9-fluorenone at 65 deg C to yield a 1:1 mixture of cis- and trans-2-deuterio-1-acenaphthenylcarbinols.Similarly, treatment of the same aluminum reagent with O2 gives a 1:1 mixture of cis- and trans-2-deuterio-1-acenaphthenols.The magnetically shielded C8 or ortho proton in the original aluminum adduct offers a valuable monitor of the extent of complexation at the C1-Al bond.The present findings demonstrate that electrophilic attack at the ortho position (leading to C3 substitution) in the kinetically controlled process, while rearrangement to C1 is thermodynamically determined.
