765-80-0Relevant academic research and scientific papers
The reaction of some polycyclic halides with lihium p,p'-di-tert-butylbiphenyl
Stapersma, J.,Kuipers, P.,Klumpp, G. W.
, p. 213 - 218 (2007/10/02)
3-chloroquadricyclane (1), 2(4)-chlorosemibullvalene (2a), a series of 2-norbornyl halides and 4,4-dichlorotetracyclo2,8.03,6>octane (4) have been treated with lithium p,p'-di-tert-butylbiphenyl.Lihiation (2, norbornyl halides), lithiation with rearrangement (4) and lithiation with rearrangement followed by reduction to the cycloheptatrienyl trianion (1 -> 14) have been found to occur.
Temperature Effects on the Selectivity of ?-Radicals
Giese, Bernd,Stellmach, Joachim
, p. 3294 - 3302 (2007/10/02)
Bent ?-radicals 3a-i, generated from alkylmercuric salts 1 and/or peresters 2, were treated with a BrCCl3/CCl4 competition system at different temperatures.Exner-analysis of these selectivity data (table 1) shows, that radicals of sp2 type 3a-d and bridgehead radicals 3e-i follow different isoselective relationships (figure 1, 2).Reversal of the selectivity row occurs at 310 and 210 K, respectively.Above of these isoselective temperatures less shielded radicals are more selective than more shielded radicals because entropy effects overcompensate enthalpy effects (table 2).Comparison with ?-radicals 6 shows, that each type of carbon radicals follows an isoselective relationship by its own.
