Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, USA.
J Am Chem Soc. 2010 Mar 24;132(11):3793-807. doi: 10.1021/ja909371t.
The first systematic mechanism study of C-F reductive elimination from a transition metal complex is described. C-F bond formation from three different Pd(IV) fluoride complexes was mechanistically evaluated. The experimental data suggest that reductive elimination occurs from cationic Pd(IV) fluoride complexes via a dissociative mechanism. The ancillary pyridyl-sulfonamide ligand plays a crucial role for C-F reductive elimination, likely due to a kappa(3) coordination mode, in which an oxygen atom of the sulfonyl group coordinates to Pd. The pyridyl-sulfonamide can support Pd(IV) and has the appropriate geometry and electronic structure to induce reductive elimination.
本文首次对过渡金属配合物中 C-F 还原消除的机理进行了系统研究。对三种不同的 Pd(IV)氟化物配合物的 C-F 键形成进行了机理评估。实验数据表明,还原消除是通过阳离子 Pd(IV)氟化物配合物的解离机制发生的。辅助吡啶-磺酰胺配体在 C-F 还原消除中起着关键作用,这可能是由于其κ(3)配位模式,其中磺酰基的一个氧原子与 Pd 配位。吡啶-磺酰胺可以稳定 Pd(IV),并且具有合适的几何形状和电子结构来诱导还原消除。