84. Benzcyclooctatetraenes. Part I

AN ATTEMPTED SYNTHESIS OF A CYCLOÖCTATETRAENE. CIS-TRANS ISOMERISM OF SUBSTITUTED DI- AND TRI-PHENYLBUTADIENES1

“…Finally there was no evidence of the formation of an unstable intermediate product of the type postulated in (c). The recently reported failure of Rapson and Shuttleworth (21) to obtain 1,2,3,4-dibenzocyclooctatetraene by the action of metallic copper on 1,4-bis-(o-iodophenyl)-l,3-butadiene must on the other hand be attributed to the geometrical configuration of their intermediate. This diiodo compound was almost undoubtedly trans-trans since it was obtained directly from a Kuhn-Winterstein modification of the Perkin synthesis.…”

The Chemistry of Eight-Membered Carbocycles.

“…Several unsuccessful attempts have been made to synthesize cyclooctadibenzene compounds, such as the condensation of 2,2'-biphenylcarboxaldehyde with ethyl succinate (112), ring-closure of 1,4-di(2-iodophenyl)-l ,3-butadiene (112) by the Ullmann reaction, and intramolecular coupling of the diazonium salt of 1 -(2-aminophenyl)-4-phenyl-1,3-butadiene (4).…”

Ester, Ether, and Carbonyl Functions as ortho Participants in the Dissociation of Iodobenzene Dichloride

“…Solvents other than acetic acid were used in unsuccessful attempts to obtain this material in purer form. 6 The pure iodo compound melts at 100-101°. It is possible that in this case the solid dichloride loses chlorine completely before melting occurs.…”

“…These initial concentrations ranged, respectively, from 2 X 10-1 to 2 X 10 "2 M and from 0.03 to 0.15 M in the various runs which are summarized in the table. 6 From ref. sufficiently positively polarized by the aromatic ring so that the carbonyl oxygen cannot release electrons to iodine in the activation process.…”