370868-03-4Relevant academic research and scientific papers
O-DPPB-directed copper-mediated and -Catalyzed allylic substitution with grignard reagents
Demel, Peter,Keller, Manfred,Breit, Bernhard
, p. 6669 - 6683 (2008/09/16)
The ortho-diphenylphosphanylbenzoyl (o-DPPB) group was explored as a directing leaving group in copper-mediated and copper-catalyzed allylic substitution with Grignard reagents. Complete control of chemo-, regio- and stereoselectivity with complete syn-1,3-chirality transfer was observed as a result of the directed nature of the reaction. No excess of or ganometallic reagent is required and the directing group can be recovered quantitatively. Coordination studies in the solid state and in solution have shown that two substrates are bound via the phosphine function of the directing group at copper. Dynamic NMR experiments in solution are in agreement with a ligand-exchange process at copper, a prerequisite for the development of a substoichiometric process.
Copper-Mediated and -Catalyzed o-DPPB-Directed Allylic Substitution
Breit, Bernhard,Demel, Peter
, p. 429 - 432 (2007/10/03)
Complete control of chemo-, regio- and stereoselectivity in the course of copper-catalyzed and -mediated allylic substitution could be obtained with me ortho-diphenylphosphanyl (o-DPPB) function as a reagent-directing leaving group. Complete chirality transfer by way of a syn-addition process has been achieved for cyclic and acyclic systems. Readily available Grignard reagents may be employed as nucleophiles and the directing o-DPPB group can be recovered quantitatively. The reaction requires neither cooling nor an excess of organometallic reagent.
