Development of Novel Phosphino-Oxazoline Ligands and Their Application in Asymmetric Alkynlylation of Benzylic Halides

Comprehensive Summary A new set of stereochemically diverse phosphino-oxazoline ligands derived from simple L-amino acids and 2-(diphenylphosphaneyl)benzoic acid were developed. Those mono anionic tridentated N,N,P-ligands promote the Cu-catalyzed enantioselective radical coupling of terminal alkynes with a broad range of benzylic halides including benzo-fused cyclic alpha-halides and alpha-silyl benzyl halides in high yield and excellent enantioselectivity under mild reaction conditions. With multi distinct sites for structural modification, a diverse pool of chiral N,N,P-ligands is readily accessed, allowing for rapid optimization of the ligand structure for a specific substrate. Notably, the enantioselective alkynlylation of benzylic halides bonds in benzo-cyclic molecules has also been realized for the first time.

Automated summary

A new set of stereochemically diverse phosphino-oxazoline ligands derived from simple L-amino acids and 2-(diphenylphosphaneyl)benzoic acid were developed. These mono anionic tridentated N,N,P-ligands promote the Cu-catalyzed enantioselective radical coupling of terminal alkynes with a broad range of benzylic halides in high yield and excellent enantioselectivity under mild reaction conditions. Notably, the enantioselective alkynlylation of benzylic halides bonds in benzo-cyclic molecules has also been realized for the first time.