Tuning StackPhim Ligands: Applications in Enantioselective Borylation and Alkynylation

Abstract

In this manuscript we present a new Stack-Ligand with a modified imidazoline backbone prepared from cyclohexane diamine. This new Stack-Ligand, Cy-StackPhim, has been found to complement the parent StackPhim ligand in an enantioselective borylation reaction. Additionally, a correlation between the nature of substituents on the imidazoline ring and the substituents on the electrophile is also discussed.

Enantioselective Synthesis of Allylic Sulfones via Rhodium-Catalyzed Direct Hydrosulfonylation of Allenes and Alkynes

“…In our laboratories, a series of chiral P,N-ligands have been under development. The ligands are axially chiral and incorporate a five-membered N-heterocycle in StackPhos ( L6 ) and StackPhims ( L7 and L8 ) . Although these ligands have proven themselves to be exceptional for copper-catalyzed enantioselective alkynylation reactions, the impact that Stack ligands impart in other transition-metal-catalyzed reactions is still virtually unexplored and of great interest, especially considering that within the family of ligands the position of phenyl substituents on the imidazole/imidazoline ring changes, which could potentially change the intrinsic reactivity of the ligands, impacting the reaction profile .…”