Unusual bridgehead reactivity: Formation of [1.1.1]Propellane by 1,3-dehydrobromination of 1-bromobicyclo[1.1.1]Pentane.
作者:Ernest W. Della、Dennis K. Taylor、John Tsanaktsidis
DOI:10.1016/s0040-4039(00)97847-x
日期:1990.1
The reaction between -butyllithium and 1-bromobicyclo[1.1.1]pentane is characterised by 1,3-dehydrobromination and gives [1.1.1]propellane . In the presence of -butyllithium, undergoes ring-opening and yields 3--butylbicyclo[l.l.1]pentyllithium .
Adcock, William; Binmore, Gavin T.; Krstic, Alexander R., Journal of the American Chemical Society, 1995, vol. 117, # 10, p. 2758 - 2766
作者:Adcock, William、Binmore, Gavin T.、Krstic, Alexander R.、Walton, John C.、Wilkie, John
DOI:——
日期:——
Bridgehead Carbocations: A Solvolytic Study of 1-Bromobicyclo[1.1.1]pentane and Its Bridgehead-Substituted Derivatives
作者:Ernest W. Della、Cyril A. Grob、Dennis K. Taylor
DOI:10.1021/ja00093a014
日期:1994.7
The rate constants (k) for solvolysis of a range of 3-X-substituted bicyclo[1.1.1]pentyl bromides in 80% aqueous ethanol have been measured and a linear relationship found to exist between log k and the inductive/field constant sigma(I). These observations, together with the results of isotope and solvent effect studies described below, have been interpreted as evidence for the formation of 1-bicyclo[1.1.1]pentyl cations in the ionization step in preference to mechanisms in which either ring-opening is concerted with ionization to give 3-methylenecyclobutyl cations or ionization is accompanied by ring-contraction to give bicyclo[1.1.0]butyl-1-carbinyl cations. The latter mechanisms would have been expected to show the effects of strong pi-donor substituent participation, a phenomenon which was not observed. A comparison of the rates of solvolysis of the parent bromide and its 3-deuterated analog is characterized by a large deuterium-isotope effect (k(H)/k(D) = 1.30) which, combined with the observation that 1-bromobicyclo[1.1.1]pentane solvolyses with enhanced rates in solvents which are strong hydrogen bonding accepters, lends support to the view that the 1-bicyclo[1.1.1]pentyl cation derives substantial stabilization from sigma-hyperconjugative interactions.
DELLA, ERNEST W.;TAYLOR, DENNIS K., AUSTRAL. J. CHEM., 43,(1990) N, C. 945-948
作者:DELLA, ERNEST W.、TAYLOR, DENNIS K.
DOI:——
日期:——
DELLA, ERNEST W.;TAYLOR, DENNIS K.;TSANAKTSLDLS, JOHN, TETRAHEDRON LETT. , 31,(1990) N6, C. 5219-5220
作者:DELLA, ERNEST W.、TAYLOR, DENNIS K.、TSANAKTSLDLS, JOHN