246-92-4Relevant articles and documents
Formation of cyclopent[a]indene and acenaphthylene from allyl esters of biphenyl mono- and di-carboxylic acids and from biphenyl dicarboxylic anhydrides on flash vacuum pyrolysis at 1000-1100°C
Bapat, Jayant B.,Brown, Roger F.C.,Bulmer, Glenn H.,Childs, Trevor,Coulston, Karen J.,Eastwood, Frank W.,Taylor, Dennis K.
, p. 1159 - 1182 (2007/10/03)
Flash vacuum pyrolysis at 1000-1100°C of the allyl esters of the three isomeric biphenylcarboxylic acids, of the allyl esters of the 12 biphenyldicarboxylic acids and of the three biphenyldicarboxylic anhydrides gave pyrolysates which were examined by 1H n.m.r. spectroscopy at temperatures below -50°C. In all cases the spectra showed the presence of cyclopent[a]indene and acenaphthylene together with other products. Possible mechanisms for these ring contraction and cyclization processes are discussed and the results of pyrolyses of [2,3-13C2]biphenyl-2,3-dicarboxylic anhydride, and [3,4-13C2]-and (2-2H1)-biphenyl-3,4-dicarboxylic anhydrides are reported.
Cyclopentindene (Benzopentalene) and Pentalene: Pyrolytic Formation from 3-Phenyl- and 3-Vinyl-phthalic Anhydrides
Brown, Roger F. C.,Choi, Neil,Eastwood, Frank W.
, p. 185 - 198 (2007/10/02)
Pyrolysis of 3-phenylphthalic anhydride at 900 deg/0.02 mm gives cyclopentindene, characterized by 1H n.m.r. at -70 deg and by formation of a cyclopentadiene adduct and of a dimer at room temperature.Pyrolysis of 3,4-, 3,5- and 3,6-diphenylphthalic anhydrides also gives much cyclopentindene by loss of the additional phenyl group. 3,4-diphenylphthalic anhydride forms triphenylene as the major product.The pyrolysate from 3-vinylphthalic anhydride contains the known dimer of pentalene, and phenylacetylene.Pyrolyses of 3-(1-naphthyl)phthalic anhydride and of 4-phenylphenanthrene-2,3-dicarboxylic anhydride are described.
Cyclopentindene (Benzopentalene): Generation by Flash Vacuum Pyrolysis and Subsequent Dimerisation
Brown, Roger F. C.,Choi, Neil,Coulston, Karen J.,Eastwood, Frank W.,Wiersum, Ulfert E.,Jenneskens, Leonardus W.
, p. 4405 - 4408 (2007/10/02)
Cyclopentindene (benzopentalene, 7) is generated by flash vacuum pyrolysis of 3-phenylphthalic anhydride (6), biphenylene (3) or diphenic anhydride (4).It dimerises readily and adds cyclopentadiene above -70 deg C, but it does not equilibrate at 900 deg C with as-indacene (1).
