359001-75-5Relevant academic research and scientific papers
Diastereoselective remote C-H activation by hydroboration
Varela, Jesus A.,Pena, Diego,Goldfuss, Bernd,Denisenko, Dmitri,Kulhanek, Jiri,Polborn, Kurt,Knochel, Paul
, p. 4252 - 4264 (2007/10/03)
Hydroboration of tetrasubstituted or trisubstituted alkenes with BH 3 and subsequent thermolysis allows remote diastereoselective C-H activation of neighboring aryl rings. Tetrasubstituted and trisubstituted 1,1-diphenyl-ethylene derivatives undergo a highly stereoselective 1,2-rearrangement followed by remote C-H activation to lead, after oxidative workup, to a diol in which the relative stereochemistry of two stereocenters has been controlled. The mechanism of this remote activation has been studied and extended to related molecules that undergo this stereoselective C-H activation, namely alkenylbiphenyl systems or alkenes with only one phenyl ring, such as alkenylbenzenes. or bicyclic systems. We have shown that this reaction allows diastereoselective synthesis of molecules with up to three contiguous chiral centers.
Three-electron S(N)2 reactions of arylcyclopropane cation radicals. 2. Steric and electronic effects of substitution
Dinnocenzo,Zuilhof,Lieberman,Simpson,McKechney
, p. 994 - 1004 (2007/10/03)
The nucleophilic substitution reactions on substituted arylcyclopropane cation radicals were studied by a combination of methods including product studies, time-resolved laser flash photolysis, kinetic isotope effects, and quantum chemical calculations. The reactions were found to proceed stereospecifically with inversion of configuration, with high regioselectivity for nucleophilic attack at the more substituted carbon atom, and with very small steric effects. Electronic effects on the nucleophilic substitution regiochemistry and the rate constants were found to be substantial for substituents on the cyclopropane moiety and on the aryl ring.
