Stereospecific Cross Couplings To Set Benzylic, All-Carbon Quaternary Stereocenters in High Enantiopurity.
Asymmetric preparation of all-carbon quaternary stereocenters is an important goal. Despite advances in formation of highly enantioenriched products with quaternary stereocenters proximal to a functional group, methods to install quaternary stereocenters isolated from functional groups are limited. Transition metal catalysis offers a potential solution, but prior cross couplings are limited to allylic substrates or deliver little to no enantiomeric enrichment. We report a stereospecific, nickel-catalyzed Suzuki-Miyaura arylation of tertiary benzylic acetates to deliver products with diaryl and triaryl quaternary stereocenters in high yields and ee's. This reaction employs an inexpensive, air-stable Ni(II) salt and commercially available phosphine ligand to transform tertiary alcohol derivatives, which are easily available in exceptional ee, into valuable products with stereoretention.
Department of Chemistry & Biochemistry, University of Delaware , Newark, Delaware 19716, United States.
Qi
Q
Zhou
Department of Chemistry & Biochemistry, University of Delaware , Newark, Delaware 19716, United States.
Kelsey M
KM
Cobb
Department of Chemistry & Biochemistry, University of Delaware , Newark, Delaware 19716, United States.
Tianyu
T
Tan
Department of Chemistry & Biochemistry, University of Delaware , Newark, Delaware 19716, United States.
Mary P
MP
Watson
D002244:Carbon / Q000737:chemistry*; D002384:Catalysis; D008024:Ligands; D015394:Molecular Structure; D009532:Nickel; D010720:Phosphines; D013237:Stereoisomerism
D008024:Ligands; D010720:Phosphines; D002244:Carbon; D009532:Nickel