Effect of Tethered, Axially Coordinated Ligands (TACLs) onDirhodium(II,II) Catalyzed Cyclopropanation: A Linear Free EnergyRelationship Study

Hammett correlation experiments were used todetermine the influence of dirhodium(II,II) paddlewheel complexeswith tethered, axially coordinated ligands (TACLs) on the selectivityof rhodium carbenoids in competitive cyclopropanation reactions.The results suggest that dirhodium(II,II) paddlewheel complexeswith TACLs are less sensitive to changes in electronics and reduceselectivity in cyclopropanation reactions with acceptor-substitutedrhodium carbenoids. Also, Hammett plots with aryl diazoacetatesresulted in a nonlinear downward curvature, suggesting a change inthe rate-limiting step of the carbene transfer reaction

Automated summary

Hammett correlation experiments were conducted to investigate the influence of dirhodium(II,II) paddlewheel complexes with tethered, axially coordinated ligands (TACLs) on the selectivity of rhodium carbenoids in cyclopropanation reactions. The results indicate that dirhodium(II,II) paddlewheel complexes with TACLs are less affected by changes in electronics and decrease selectivity in cyclopropanation reactions with acceptor-substituted rhodium carbenoids. Additionally, Hammett plots using aryl diazoacetates showed a nonlinear downward curvature, suggesting a change in the rate-limiting step of the carbene transfer reaction.