1714-09-6Relevant articles and documents
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Klemm et al.
, p. 1468,1476 (1959)
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Probing mechanisms of aryl-aryl bond cleavages under flash vacuum pyrolysis conditions
Jackson, Edward A.,Xue, Xiang,Cho, Hee Yeon,Scott, Lawrence T.
, p. 1279 - 1287 (2014/11/08)
Several biaryls have been subjected to flash vacuum pyrolysis (FVP) at 1100°C and 0.8-0.9hPa. Product compositions are reported for the FVP of 9-phenylanthracene (1), 2-bromobiphenyl (5), biphenyl (8), 1,10- diphenylanthracene (12), 9-(2-naphthyl)anthracene (17), and 9,9′- bianthracenyl (20). The experimental results have been used to evaluate four possible mechanistic pathways for the cleavage of aryl-aryl bonds under these conditions: (1) the 'explosion' of substituted phenyl radicals; (2) hydrogen atom attachment to an ipso-carbon atom of the biaryl followed by C-C bond cleavage; (3) direct homolysis; and (4) loss of a fragment as an aryne. None of these mechanisms by itself successfully accommodates all of the experimental facts. The data suggest that aryl-aryl bond cleavages under FVP conditions involve at least two different mechanistic pathways and that the relative contributions of the competing pathways probably vary from one biaryl to the next.
5,6,7,12-Tetrahydrodibenz[c,f][1,5]azabismocines: Highly reactive and recoverable organo-bismuth reagents for cross-coupling reactions with Aryl Bromides
Shimada, Shigeru,Yamazaki, Osamu,Tanaka, Toshifumi,Rao, Maddali L. N.,Suzuki, Yohichi,Tanaka, Masato
, p. 1845 - 1848 (2007/10/03)
Hypervalent organobismuth compounds efficiently couple with aryl bromides in the presence of [Pd(PPh3)4] catalyst. Application of this protocol to a one-pot multi-coupling reaction with bromophenylboronic esters leads to the formation of up to nine bonds in good yields (see scheme).