P Ligands and Derivatives

Guiry and coworkers [19] reported the preparation and testing of 2,2-dimethyl-2,3-dihydrofuran (22) as an interesting substrate for the intermolecular asymmehic Mizoroki-Heck reaction as this substrate only forms the one regioisomeric product 23. This allows for a true comparative test of a range of palladium complexes, and (7 )-BlNAP 

Ligand Design for Intermolecular Asymmetric Mizoroki-Heck Reactions 411 

The reaction shows that BINAPAs (40) shows very different product ratios in comparison with BINAP, resulting in the formation of (R)-3 (29%, 82% ee) and (l )-4 (48%, 45% ee). The product ratio was changed, indicating that dissociation of the BINAPAs-Pd+-H complex from a resulting olefinic double-bond occurs more readily than that of the BINAP-Pd -H complex, favouring (/J)-2-phenyl-2,5-dihydrofuian 4 as the major product. 

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