116204-83-2Relevant academic research and scientific papers
Novel synthesis of biphenylene and its derivatives using intramolecular coupling of zincacyclopentadienes
Iyoda, Masahiko,Kabir, S. M. Humayun,Vorasingha, Anusorn,Kuwatani, Yoshiyuki,Yoshida, Masato
, p. 5393 - 5396 (1998)
Biphenylene and its derivatives were synthesized using the intramolecular coupling of benzoannelated zincacyclopentadiene intermediates prepared from 2,2'-dilithiobiaryls with ZnCl2. The reaction proceeded smoothly and selectively to give the desired biphenylenes in moderate to good yields.
Synthesis of biphenylenes and tetraphenylenes using copper-catalyzed coupling of arylzinc intermediates
Kabir, S.M. Humayun,Hasegawa, Masashi,Kuwatani, Yoshiyuki,Yoshida, Masato,Matsuyama, Haruo,Iyoda, Masahiko
, p. 159 - 165 (2007/10/03)
Biphenylene and some of its 2,3,6,7- and 1,8-substituted derivatives were synthesized using the CuCl2-mediated intramolecular coupling of an organozinc species prepared from 2,2′-dilithiobiaryls with one or two molar equiv. of ZnCl2 or ZnBr2 in THF. Although most of the reactions of 2,2′-dilithiobiaryls with CuCl2 in THF in the absence of ZnCl2 or ZnBr2 led to biphenylenes as a major product, similar reactions of the organozinc species with CuCl2 in THF produced biphenylenes in much better yields, due to smooth transmetallation and reductive elimination reactions. In particular, the copper-mediated cyclization of benzannelated organozinc intermediates, prepared from equimolar proportions of 2,2′-dilithiobiaryls with ZnCl2, proceeded smoothly and selectively to afford the desired biphenylenes in 46-81% yield except for the reaction of the zinc intermediate derived from 4,4′,5,5′-tetramethoxy-2,2′-dilithiobiphenyl with ZnCl2 (1.0 molar equiv.). The reaction of the tetramethoxy-substituted organozinc species with CuCl2 produced 2,3,6,7,10,11,14,15-octamethoxytetraphenylene as a major product in 67% yield.
