Nguyen MH.
O’Brien KT.
Smith III AB.
* University of Pennsylvania, Philadelphia, USA
Design, Synthesis, and Application of Polymer-Supported Silicon-Transfer Agents for
Cross-Coupling Reactions with Organolithium Reagents.
J. Org. Chem. 2017;
82: 11056-11071
Key words
silicon - organolithium reagents - palladium catalysis - cross-coupling - transfer
agents
Significance
Polymer-supported siloxanes were developed as transfer agents for cross-coupling reactions
involving organolithium reagents. For example, the polystyrene-supported siloxane
1 was treated with an aryl or alkenyl lithium 2, and the resulting material was treated with an aryl halide 3 in the presence of PdCl2, CuI, and ligand L to give the corresponding product 4 in 68–97% yield.
Comment
The transfer agent 1 was recovered almost quantitatively by simple filtration and rinsing, and reused
in the cross-coupling several times. No cross-contamination of the products 4 was detected in a series of ten reactions with recycled 1 and various combinations of organolithium reagents 2 and aryl halides 3.
