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Abstract Herein, we leverage the Ni‐catalyzed enantioselective reductive dicarbofunctionalization of internal alkenes with alkyl iodides to enable the synthesis of chiral pyrrolidinones bearing vicinal stereogenic centers. The application of newly developed1‐NapQuinim is critical for formation of two contiguous stereocenters in high yield, enantioselectivity, and diastereoselectivity. This catalytic system also improves both the yield and enantioselectivity in the synthesis of α,α‐dialkylated γ‐lactams. Computational studies reveal that the enantiodetermining step proceeds with a carbamoyl‐NiIintermediate that is reduced by the Mn reductant prior to intramolecular migratory insertion. The presence of thet‐butyl group of the Quinim ligand leads to an unfavorable distortion of the substrate in the TS that leads to the minor enantiomer. Calculations also support an improvement in enantioselectivity with1‐NapQuinim compared top‐tolQuinim.
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Copper‐Phosphido Catalysis: Enantioselective Addition of Phosphines to Cyclopropenes**
Abstract We describe a copper catalyst that promotes the addition of phosphines to cyclopropenes at ambient temperature. A range of cyclopropylphosphines bearing different steric and electronic properties can now be accessed in high yields and enantioselectivities. Enrichment of phosphorus stereocenters is also demonstrated via a Dynamic Kinetic Asymmetric Transformation (DyKAT) process. A combined experimental and theoretical mechanistic study supports an elementary step featuring insertion of a CuI‐phosphido into a carbon‐carbon double bond. Density functional theory calculations reveal migratory insertion as the rate‐ and stereo‐determining step, followed by asyn‐protodemetalation.
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- PAR ID:
- 10433910
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Angewandte Chemie
- Volume:
- 135
- Issue:
- 36
- ISSN:
- 0044-8249
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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